This was a perfect example of why so many of us love your channel. You are a man of integrity and great diagnostic skill. Not to forget that you are an excellent communicator. Thank you, as always, brother.
Great work Ahmed, our 3rd generation is running strong that you repaired (head gasket, egr pump, egr valve, intake manifold, water pump, etc...). You are by far the best mechanic I’ve ever had the privilege of dealing with. May GOD richly bless you for your integrity and hard work. Sean L.
@@richardvargus7443 sir, I bought the car with 160,000 miles, it a car for our son. We got the car cheap, and knew we would need to put a little money into it, thus we took it to Ahmed whom was much less expensive than anyone I got estimates from including the dealer.
AMD, you are spot on with concluding why the pistons are steam cleaned. It's been a while, and then it developed into a more extensive leak. The Prius has an Atkinson cycle integrated into the stroke, and for a normal engine, that would not occur, but with the Prius, your conclusion is spot on.
Great job Ahmed! It always pays to check something out in more detail when what you find initially does not make sense. You are a true engineer and mechanic! 👍
Dear car care nut I own a 2019 Corolla with the 2,0 hybrid engine and had the exactly same issue. The heat Converter in the exhaust had a coolant leak. I live in denmark and been following you for quit a while. Keep up your great work on your Channel. I’m enjoying watching your videos a lot, as a Toyota afficonado. Greetings Erling
A technician like yourself that has experience with the product as well as excellent deductive reasoning skills is worth his weight in gold! Excellent diagnosis and explanation of how you found the problem as usual. Way to go Ahmed!
Great diagnostic job! Finding out what the problem is BEFORE taking the engine apart, thereby having to take extra time, and costing the customer extra money. I wish that there was someone just like you here on Oahu. If there was I would definitely give them my business. Please continue to make these awesome videos!
I knew right what it was from the beginning of the video. Saw one at the dealership and Toyota actually issued a TSB for these, they updated the heat exchanger pipe.
I am 82 years old and do EVERYTHING MYSELF EXCEPT TRASMISIONS.If I lived near you ,I would relax and have you do ALLof my work. You are a true craftsman
Exhaust blowback getting into cylinders is exactly what I was thinking once I saw the coolant coming out the pipe. But, with the cost of OEM Toyota Cats, I’m not sure how much better your news is LOL
It's a common problem for cars with lots a mileage. We had this problem 2 years ago and Again and again. We seen a lot of this. Every Prius 2016+ have this problem. Also all Corolla and C-HR with 2 liters engine have this issue.
And this is why you are a MASTER tech and I watch your channel. You figure out problems and don't just charge the customer. To bad you in Chicago area and not by me.
One of your best videos yet, hats off. I always learn something new watching you videos, even having 30 plus years of experience with mechanical gadgets. Now could you not just bypass that system to complete some testing in the rest of the engine and find out if its working with no problems?
It was very enlightening to see your careful step-by-step process and analysis in addressing this problem. Your narrative and explanation of what you were finding, as well as your expressions of curiosity at each step of the way until you arrived at a conclusion that could account for what you were finding, was both entertaining and educational. A great piece of detective work. Two Thumbs Up! 👍👍
Great diagnostic!! I would wager that the average shop would have done as you mentioned. Seen the steam cleaned pistons tops and sold a head gasket replacement job and then been faced with the cat issue! We so many more of you, Eric O, and Ivan’s in the world of mechanics. The public also needs to understand that in this day and age diagnostic time is money well spent. Great diagnostic. Wish you and your family a great new year.
That was a really good one. As soon as I saw all four cylinders clean with no leaks, I suspected a that the head gasket was fine. Besides, they don't usually fail everywhere at once. As you said, the EGR assembly mimicking exhaust valve timing would allow the pistons to get steam cleaned without misfires. What an awesome diagnosis, and one lucky customer!
Good and Bad news for the owner, I usually associate Prius Head gasket issues with the morning death rattle and will always throw engine codes for misfire and rarely use that much coolant in one day. That cooler is a known problem on the 3rd gen Prius, I just worked on one this week. Good to know that they still have not resolve on the 4th gen.
I enjoy witnessing your process of seeking answers to your inquiries-it reflects the meticulous approach of scientists, never making assumptions. Fantastic video on accurate diagnosis!👍
Thanks for the video as always, excellent job . I had a similar problem with a Toyota Corolla , every dealer I took it, they all gave me a different diagnosis. I had to sell it because that engine light, never when out and it couldn’t pass inspection. I wish I had you as a mechanic. Thanks again excellent job.
Amazing diagnotics and logical skills AMD, you sir are the SHERLOCK HOLMES of automative service, thank you for taking us on another wonderful journey. God bless!!
Great video! I have an '87 560SEC Benz that has a slower water leak than this Prius but also no apparent sources. I was going to pull all eight plugs and see if any looked too clean but your video taught me that using my borescope to look into the cylinders is a very good thing and what to look for. I just ordered a radiator pressure kit that will be delivered tomorrow, so I can pressurize the cooling system without having to get the engine up to temperature. My intake manifold had been removed and reinstalled to replace a bunch of plastic and rubber bits and...coolant does go through the manifold. All-in-all, you have provided me with a clear path forward!! Thanks!!!
Actually received a recall letter on my KIA NIRO HEV for the same issue! My coolant has been dropping very slowly during summer days and when I mentioned to the advisor he said that a same model came in and was losing it daily and found all of them went into the catalytic converter!
Thank you. What a relief that it is not HG issue. I have 2018 Prius Prime that is suffering from the similar issue at 170000 km. It smokes white once in a while but runs great. The coolant loss has been manageable.
Kudos on the ability to objectively assess the available evidence gathered and not jump straight to a conclusion, especially in front of a rolling camera!
Excellent to see the disgnostic process and the actual physical damage, as well as the explanation. Hybrids are a Wonder of the Automotive World, requiring specialized mechanics we can trust: unfortunately, all mechanics are not like AMD, Scotty Kilmer, and others we can see on UA-cam, or that are about to retire close to where we live. And, I forgot the dealers...yes, is maybe, because, is sad to recognize, we need to forget about the dealer, if you want your car to last a long time, because they have the conflict of interest, of trying to sell you a new car sooner than later, and having yours in a trade in, that could be called, a steal in....
@@gianfrancoa Scotty Kilmer is a recognized trusted mechanic. There are many we cannot trust, the World needs more people who tell the truth, without receiving money from corporations trying to sell through comnercials and public relations.
There are some excellent techs at the dealerships, but they are caught between the flat rate system & the dealership owner's policy. If all the owner cares about is money - guess what? The 2nd time I went to a dealer was for a recall that they did with no charge, but the lug nuts were tightened more than 40ft.lbs. OVER the specified spec. That was a tech using a impact gun without using a torque wench! I will be going back there to let them know that I rechecked (after watching a UA-cam video about wheel studs) the torque.
@@pablorosado535 There is nothing that you can learn from Scotty other than screaming throughout his video . Just a cheap show . Ahmed is a true technician to learn from .
Same exact thing happened with my 2017 Two in June. We were driving home at night and the wife was cold so she turned up the heat. Never got hot, then the warning light came on. FIL is a Toyota tech, so I took it to him the next day and he said it was this issue. Good thing it was a warranty job because CA…didn’t want to see the bill on that one lol. There’s also a TSB on this issue, and a replacement that supposedly fixes the issue, but it’s only to be completed when the issue shows up, which is a bummer because this could blow the engine if someone isn’t paying attention to the coolant, like myself, and who doesn’t have anyone to take it to right away.
Great diagnostic work Ahmed, that is why you are a Toyota Master Diagnostic Technician. The owner can park that thing in Chicago overnight and someone will remove that catalytic converter with no charge 😁, got to love Chicago.
Not that big of a mystery. Anytime there is a loss of coolant that is not external, that is not leaving evidence of coolant under the vehicle, the source has to be in the engine. Most V type engines (excepting "dry" manifold types) have coolant passages in the intake manifold, the gasketed joints where the manifold joins the head are a common source especially with plastic intake manifolds when manufacturers "went cheap" and stopped using aluminum or iron intakes. These leaks typically are into the oil resulting in the oil having a "milky" appearance. Far more rare are leaks through coolant heated throttle bodies (GM loved using those) and coolant heated carburetor spacers (Ford FE engines from 1958-70) The purpose was to prevent carburetor/throttle body icing in cold and humid conditions. Rare in the age of iron-over-iron engines, head gasket failures have become an issue because of aluminum heads, and the simple fact of physics that iron and aluminum do not expand and contract at the same rate, as a result newer types of head gaskets and the idiocy of torque-to-yield head fasteners have become common. EGR, whether cooled or not causes more problems than its worth, the intent is reduction of nitrous oxide in the exhaust, but results in lessened fuel economy, increased intake deposits and reduced performance. I definitely would delete the EGR system if it had the potential of leaking coolant into the engine or exhaust as it did in the video.
@@JR-tl8tg This will be a long upload, but it is the diagnostic procedure I would follow. What I would do first is to carefully inspect the joint between the head and block as well as all freeze plugs in the block for any evidence of a white colored residue which would be indicative of a small and slow leak, as these are the most common locations for seepage/leaks after hose issues. It may require a mechanics mirror to inspect some of the areas as they are not easily able to be inspected, especially under/behind exhaust manifolds. This goes without saying....make sure your heater core is in good shape (not a common problem on Toyota vehicles) Also look under the oil filler cap and the upper part of the oil dipstick for any sign of a milky substance, which can be indicative of coolant leaking into the oil, but be aware that if you are in a humid climate that may be caused by simple condensation. If your throttle body has no coolant lines going to it (they will be small diameter hoses, most likely 10mm or 3/8 in) then it does not have a heated throttle body, and therefore would not be a potential leak source. Im in all honesty not sure about whether your engine has a heated throttle body or not as the engine repairs I have done to Toyota/Lexus SUV engines have not involved an issue of that type that could not directly be assigned to a leaking water pump. leaking hoses/radiator seams or a failed head gasket. Also be aware that the water pump is concealed under covers and may be seeping without obvious signs of coolant on below the vehicle, this issue I have seen and repaired on Toyota engines. If no leak has been detected at this point, removal of the spark plugs and inspection of the combustion chamber and pistons is the next step as per the video. If either have little or no carbon deposits that is an indication of coolant leakage into that cylinder, which is strongly indicative of a blown head gasket or cracked cylinder head.......However...... Toyota generally designed and manufactured cylinder heads which were thicker and more robust than most other manufacturers which helped to lessen head gasket issues, but failure is nevertheless a possibility, especially if the engine has ever been overheated. Ive done mechanical and transmission repair and rebuilding since 1972 on almost all vehicles..
Hello AMD, every time I watch your videos I learn something new from you. You obviously were once a great mechanical 'student' and now you have become a great 'educator'. Thank you for an incredible video Professor AMD. You are to be commended! Is it AMD or is it Ahmed?
I have a 2016 Toyota Prius that has over 240,000 mi on it. Have not seen it on that Prius holding my breath that it never happens. I have had to replace the water pump at 150,000 mi because it ended up failing on it, but other than that it's been a very reliable car
Figure out a way to monitor your engine temperature real-time with a Bluetooth diagnostic dongle or scanguage, at your mileage you may want to replace or clean your egr/exhaust gas recirculation as they coke up pretty badly by that mileage.
There was a TSB some time ago to replace that catalytic converter pipe. The coolant runs past there to accelerate heat up since the engine doesn't run under certain conditions.
Great video on proper diagnosis. I love watching you getting answers to your thoughts. Its the way scientists work. Never assuming anything. Only fact driven 🥳
Great info..! I'm sure most of us will appreciate knowing this before replacing a head gasket just to find out it didn't fix it ..! Can you imagine! What do we tell the customer? Thanks again for this very helpful video.
As you were diagnosing the coolant leak with all 4 cylinders clean my question became what is common to all cylinders. Did not expect a leak in the exhaust but back pressure from the EGR made sense. Good diagnostics.
Great video, walking us through the diagnosis. Keep going until you have an explanation for all the symptoms, and resisting the temptation to make the analysis fit the assumed cause.
Great video, what do you think caused the catalytic convertor coolant leak? I'd love to see a follow up on this repair and an autopsy of the broken part/leak to figure out what possibly caused it. I love watching your channel Ahmed. Thank you again.
Theres a valve in the cat that redirects coolant back to the engine after heating, it leaks. You can bypass it with a tube/hose plus fittings but you lose the quicker warm up and efficiency of this system, or you replace the cat assembly with the new updated version.
Awesome analysis and thanks for walking us through your reasoning for why this might not be a head gasket. That's definitely something that could be missed if someone would have gone immediately with the head gasket replacement.
Great video. If past warranty, you can bypass the coolant lines to the heat exchanger. One in engine compartment, or two, or underneath where the exchanger IS. Gasket Masters shows u on two videos. ALOT cheaper.
Great video My 2010 Prius had a blown head gasket around 300k miles I was putting in head head gasket fix until it was rear ended. I have a 2017 now and changed the coolant at 100k so it doesn’t become acidic.hoping it helps with gasket life. Also a coworker has 2017 Prius prime and her catalytic converter had the same issue. As I was watching the video I was talking to the screen to check the exhaust system
Thank you very much for sharing your experience. One note, in case of such a significant coolant lose, the first thing I wold do is oil inspection for "milk shake". If oil is clean, its a pretty good indication on healthy head gasket. 100% agree with you on the phenomenon of the shiny pistons, probably caused by exhaust back pressure saturated in steaming coolant. Thank you sir.
AMD, these cars have a tube that goes from the caralytic converter to the EGR and the gases reburn into the chamber. In this case the coolant is going to the chamber through the tube and EGR.
That is also true. That’s why if catalytic converter on those Toyota engines gets internally destroyed the small dust and pieces get returned into it the cylinders and from there destroy the engine for short time.
When my 1999 Camry 5S-FE blew its head gasket a couple of years ago, gas bubbles were pushed through the cooling system and became visible in the reservoir.
I thank-you in advance for also posting the repair video...I suspect it may be in the whelm of us DIY'ers as long as we don't have bad rusty bolts in the undercarriage area!!
This just further solidifies by documentation that you are an extraordinary diagnostician Ahmed!! Did you wind up replacing the catalytic converter and such in the leaking part?
Bought a 2013 Prius v 3 92,000 miles runs beautifully, but it has this problem Took it to a place that specializes on these cars paid $60 for the diagnostic, $2000 for head gasket replacement $300 for water pump and thermostat. Also had spark plugs replaced, after driving it around throughout the day I get home and Walla same problem, took a picture of the low level coolant and sent it to the shop that did the repairs, hopefully you’ll get back to me tomorrow.
One of my favorite diagnostics videos thus far.. another was an old video from “Pine Hollow Auto Diagnostics on an Acura MDX.. and the finding was a total plot twist just like this one… Thank you always for sharing with us.
I think this is the problem with my 4th gen prius. It started losing coolant with no visible leak and runs perfectly well. I got a fixd obd2 scanner and have it reading the coolant temp and it has been within normal range. Thank you!
Hello AMD. Thank you very much for the video. Love watching you work. Can you please do a follow up in this video with what the fix is and what parts and other things you had to do to rectify the problem and the total cost of the project. As always my prayers to you and your family and your shop and shop family. Stay safe. Peace.
Please do an internet search for T-SB-0135-19. There is a PDF that explains the repair and the coverage under different Federal and State regulatory emissions warranties.
This is why car owners need to find a mechanic like you. Most mechanics would have just replaced the head gasket based on the symptoms, charged the customer and sent them on their way.
I had the exact same problem on a 2013 HiHy, and yes it was mysterious until it made sense! The slightly sweet smell from the coolant running into the hot exhaust is also misleading because makes you think about head gasket.
Hey Now the concern is if it overheated. If you make the repair the head gasket can go following week. You tell customer that information. Excellent tutorial
I had no idea that coolant pass through the cat to heat it up, wow, i would totally miss somethig like that, like you've just said, white smoke , extremely clean cylinders, head gasket, and i would be wrong, thank you for a top notch class on the prius, i loved it
This was a great video as usual. Would have been cool to show a diagram ( if there is one) of the routing for the coolant lines thru the egr/catalitic converter.
Very interesting indeed! I love it that you take us along before actually figuring out the problem, no staged "voila" diagnosis. I can't believe the exhaust/cat is cooled also, holy crap. so envious of your critical thinking/diagnosis, that cylinder scope is invaluable. Everything you said made sense, even though the problem was not making sense. Easy to understand why many would just "jump on" the head gasket diagnosis/job. What a sinking feeling when they restarted the car after the head gasket only to note the smoke. Would be even worse if they let the customer take it only to have it return the next day with an upset customer. Don't get me wrong, we have all stumbled and made errors, but this would have been a big "ooooops" for sure.
This was a perfect example of why so many of us love your channel. You are a man of integrity and great diagnostic skill. Not to forget that you are an excellent communicator. Thank you, as always, brother.
Great work Ahmed, our 3rd generation is running strong that you repaired (head gasket, egr pump, egr valve, intake manifold, water pump, etc...). You are by far the best mechanic I’ve ever had the privilege of dealing with. May GOD richly bless you for your integrity and hard work. Sean L.
That's a lot of repairs for a supposedly reliable car that's supposed to run forever with just oil changes.
@@chuckwalla2967 it has 195,000 miles
@chuckwalla2967 it's maintenence. You should be doing coolant and transmission fluid changes on every car you've ever owned.....
@@richardvargus7443 sir, I bought the car with 160,000 miles, it a car for our son. We got the car cheap, and knew we would need to put a little money into it, thus we took it to Ahmed whom was much less expensive than anyone I got estimates from including the dealer.
@Unit_450 egr cooler
This is why you are a toyota master technician. One of my favorite yet. Other shows pre diagnose then film what they found.
AMD, you are spot on with concluding why the pistons are steam cleaned. It's been a while, and then it developed into a more extensive leak. The Prius has an Atkinson cycle integrated into the stroke, and for a normal engine, that would not occur, but with the Prius, your conclusion is spot on.
Yep, I was going to say does the Atkinson cycle have anything to do with it.
Great job Ahmed! It always pays to check something out in more detail when what you find initially does not make sense. You are a true engineer and mechanic! 👍
This is channel will be at 1 million subscribers in a couple weeks. This is the fastest growing channel on UA-cam. Keep up the great work!
Dear car care nut
I own a 2019 Corolla with the 2,0 hybrid engine and had the exactly same issue. The heat Converter in the exhaust had a coolant leak.
I live in denmark and been following you for quit a while.
Keep up your great work on your Channel. I’m enjoying watching your videos a lot, as a Toyota afficonado.
Greetings Erling
Excellent work. You’re a patient professional mechanic and mentor. Thank you for sharing this experience with us. I learned so much!
A technician like yourself that has experience with the product as well as excellent deductive reasoning skills is worth his weight in gold! Excellent diagnosis and explanation of how you found the problem as usual. Way to go Ahmed!
Like how you said
"Leaking coolant faster then the intro.
That was rich
AMD, you are ONE OF A KIND! Your knowledge and patience is simply legendary!!!
You are honest mechanic ,you could have had the customers pants down 💰💰saying it’s head gasket 💰💰hope your honesty gets rewarded 👊🏼
Great diagnostic job! Finding out what the problem is BEFORE taking the engine apart, thereby having to take extra time, and costing the customer extra money. I wish that there was someone just like you here on Oahu. If there was I would definitely give them my business. Please continue to make these awesome videos!
LXS Hawaii is great. They're on Punahou St. now.
You are just the best. The world needs more people like you!
I knew right what it was from the beginning of the video. Saw one at the dealership and Toyota actually issued a TSB for these, they updated the heat exchanger pipe.
Was it covered under powertrain?
I got a 2015 Prius with 133k miles and runs excellent. Great mpg & cheap maintenance. Can’t complain
I am 82 years old and do EVERYTHING MYSELF EXCEPT TRASMISIONS.If I lived near you ,I would relax and have you do ALLof my work. You are a true craftsman
I'm 71 & feel the same way. I hope I'm ALIVE in my 80's.😂 Let alone, still get underneath in my driveway. But I will do until I can't. 😉✊️👍🖖
No wonder this fellow has a million subscribers. Diagnosis can be the hardest part of the job. No Captain parts cannon here.
Excellent presentation. Thank you. Gen 3 original owner 2012 Prius with 280,000 miles. So far no head gasket issues. Fingers crossed.
Exhaust blowback getting into cylinders is exactly what I was thinking once I saw the coolant coming out the pipe. But, with the cost of OEM Toyota Cats, I’m not sure how much better your news is LOL
It's a common problem for cars with lots a mileage. We had this problem 2 years ago and Again and again. We seen a lot of this. Every Prius 2016+ have this problem. Also all Corolla and C-HR with 2 liters engine have this issue.
And this is why you are a MASTER tech and I watch your channel. You figure out problems and don't just charge the customer. To bad you in Chicago area and not by me.
One of your best videos yet, hats off. I always learn something new watching you videos, even having 30 plus years of experience with mechanical gadgets.
Now could you not just bypass that system to complete some testing in the rest of the engine and find out if its working with no problems?
I was thinking the same thing. I now want to get under my Gen 3 and see if i have the same system
It was very enlightening to see your careful step-by-step process and analysis in addressing this problem.
Your narrative and explanation of what you were finding, as well as your expressions of curiosity at each step of the way until you arrived at a conclusion that could account for what you were finding, was both entertaining and educational.
A great piece of detective work.
Two Thumbs Up! 👍👍
Great diagnostic!! I would wager that the average shop would have done as you mentioned. Seen the steam cleaned pistons tops and sold a head gasket replacement job and then been faced with the cat issue! We so many more of you, Eric O, and Ivan’s in the world of mechanics. The public also needs to understand that in this day and age diagnostic time is money well spent. Great diagnostic. Wish you and your family a great new year.
Wow! Your customers are always in good and honest hands in your shop
I learned something new today, cats and coolant do not mixed. Nice video
You followed your gut feeling and it paid off. Great video.
That was a really good one. As soon as I saw all four cylinders clean with no leaks, I suspected a that the head gasket was fine. Besides, they don't usually fail everywhere at once. As you said, the EGR assembly mimicking exhaust valve timing would allow the pistons to get steam cleaned without misfires. What an awesome diagnosis, and one lucky customer!
The EGR valve must be pristine clean.
Too bad no one here in Rochester has your honesty and knowledge
Rochester, NY?
Good and Bad news for the owner, I usually associate Prius Head gasket issues with the morning death rattle and will always throw engine codes for misfire and rarely use that much coolant in one day. That cooler is a known problem on the 3rd gen Prius, I just worked on one this week. Good to know that they still have not resolve on the 4th gen.
I enjoy witnessing your process of seeking answers to your inquiries-it reflects the meticulous approach of scientists, never making assumptions. Fantastic video on accurate diagnosis!👍
Crazy engineering equals a crazy problem. Great video.
Love that chuckle you did when you saw the unusual scenario of coolant dripping from the exhaust pipe. I can tell you love what you do
Thanks for the video as always, excellent job .
I had a similar problem with a Toyota Corolla , every dealer I took it, they all gave me a different diagnosis.
I had to sell it because that engine light, never when out and it couldn’t pass inspection.
I wish I had you as a mechanic.
Thanks again excellent job.
Amazing diagnotics and logical skills AMD, you sir are the SHERLOCK HOLMES of automative service, thank you for taking us on another wonderful journey. God bless!!
It IS a common gen4 problem and many simply bypass the coolant lines at the cat. Often reported on Priuschat.
Great video! I have an '87 560SEC Benz that has a slower water leak than this Prius but also no apparent sources. I was going to pull all eight plugs and see if any looked too clean but your video taught me that using my borescope to look into the cylinders is a very good thing and what to look for. I just ordered a radiator pressure kit that will be delivered tomorrow, so I can pressurize the cooling system without having to get the engine up to temperature. My intake manifold had been removed and reinstalled to replace a bunch of plastic and rubber bits and...coolant does go through the manifold. All-in-all, you have provided me with a clear path forward!! Thanks!!!
This looks like a spammer, not Ahmed. Suggestions?
Actually received a recall letter on my KIA NIRO HEV for the same issue! My coolant has been dropping very slowly during summer days and when I mentioned to the advisor he said that a same model came in and was losing it daily and found all of them went into the catalytic converter!
Fantastic diagnostic. Great Job!!❤
Thank you. What a relief that it is not HG issue. I have 2018 Prius Prime that is suffering from the similar issue at 170000 km. It smokes white once in a while but runs great. The coolant loss has been manageable.
Kudos on the ability to objectively assess the available evidence gathered and not jump straight to a conclusion, especially in front of a rolling camera!
Excellent diagnosis Dr TCCN!
Great video. Just a note for editing: listening on headphones, when your voice is at normal volume your cordless hand tools are deafening!
Excellent to see the disgnostic process and the actual physical damage, as well as the explanation. Hybrids are a Wonder of the Automotive World, requiring specialized mechanics we can trust: unfortunately, all mechanics are not like AMD, Scotty Kilmer, and others we can see on UA-cam, or that are about to retire close to where we live. And, I forgot the dealers...yes, is maybe, because, is sad to recognize, we need to forget about the dealer, if you want your car to last a long time, because they have the conflict of interest, of trying to sell you a new car sooner than later, and having yours in a trade in, that could be called, a steal in....
is good that not all mechanics are like Scotty Kilmer LOL..
@@gianfrancoa Scotty Kilmer is a recognized trusted mechanic. There are many we cannot trust, the World needs more people who tell the truth, without receiving money from corporations trying to sell through comnercials and public relations.
There are some excellent techs at the dealerships, but they are caught between the flat rate system & the dealership owner's policy. If all the owner cares about is money - guess what? The 2nd time I went to a dealer was for a recall that they did with no charge, but the lug nuts were tightened more than 40ft.lbs. OVER the specified spec. That was a tech using a impact gun without using a torque wench! I will be going back there to let them know that I rechecked (after watching a UA-cam video about wheel studs) the torque.
@@pablorosado535
There is nothing that you can learn from Scotty other than screaming throughout his video . Just a cheap show . Ahmed is a true technician to learn from .
@@AJ-AJ212 I fixed my own car several times following Scotty Kilmer advice shown on his daily videos. Scotty is a real mechanic too.
Let’s get a video of your experience as a shop owner! I appreciate your perspective.
Same exact thing happened with my 2017 Two in June. We were driving home at night and the wife was cold so she turned up the heat. Never got hot, then the warning light came on. FIL is a Toyota tech, so I took it to him the next day and he said it was this issue. Good thing it was a warranty job because CA…didn’t want to see the bill on that one lol.
There’s also a TSB on this issue, and a replacement that supposedly fixes the issue, but it’s only to be completed when the issue shows up, which is a bummer because this could blow the engine if someone isn’t paying attention to the coolant, like myself, and who doesn’t have anyone to take it to right away.
Great diagnostic work Ahmed, that is why you are a Toyota Master Diagnostic Technician.
The owner can park that thing in Chicago overnight and someone will remove that catalytic converter with no charge 😁, got to love Chicago.
AMD, I am confident the mystery will not take long to resolve and I bet 940,000 people agree with me. 😁
Not that big of a mystery. Anytime there is a loss of coolant that is not external, that is not leaving evidence of coolant under the vehicle, the source has to be in the engine.
Most V type engines (excepting "dry" manifold types) have coolant passages in the intake manifold, the gasketed joints where the manifold joins the head are a common source especially with plastic intake manifolds when manufacturers "went cheap" and stopped using aluminum or iron intakes. These leaks typically are into the oil resulting in the oil having a "milky" appearance.
Far more rare are leaks through coolant heated throttle bodies (GM loved using those) and coolant heated carburetor spacers (Ford FE engines from 1958-70)
The purpose was to prevent carburetor/throttle body icing in cold and humid conditions.
Rare in the age of iron-over-iron engines, head gasket failures have become an issue because of aluminum heads, and the simple fact of physics that iron and aluminum do not expand and contract at the same rate, as a result newer types of head gaskets and the idiocy of torque-to-yield head fasteners have become common.
EGR, whether cooled or not causes more problems than its worth, the intent is reduction of nitrous oxide in the exhaust, but results in lessened fuel economy, increased intake deposits and reduced performance. I definitely would delete the EGR system if it had the potential of leaking coolant into the engine or exhaust as it did in the video.
@@donreinke5863fail
@@donreinke5863 interesting, would this apply to the 2GR-FE RX350 mine seems to be losing coolant in small amounts but I can't find the leaks.
@@JR-tl8tg
This will be a long upload, but it is the diagnostic procedure I would follow.
What I would do first is to carefully inspect the joint between the head and block as well as all freeze plugs in the block for any evidence of a white colored residue which would be indicative of a small and slow leak, as these are the most common locations for seepage/leaks after hose issues.
It may require a mechanics mirror to inspect some of the areas as they are not easily able to be inspected, especially under/behind exhaust manifolds.
This goes without saying....make sure your heater core is in good shape (not a common problem on Toyota vehicles)
Also look under the oil filler cap and the upper part of the oil dipstick for any sign of a milky substance, which can be indicative of coolant leaking into the oil, but be aware that if you are in a humid climate that may be caused by simple condensation.
If your throttle body has no coolant lines going to it (they will be small diameter hoses, most likely 10mm or 3/8 in) then it does not have a heated throttle body, and therefore would not be a potential leak source.
Im in all honesty not sure about whether your engine has a heated throttle body or not as the engine repairs I have done to Toyota/Lexus SUV engines have not involved an issue of that type that could not directly be assigned to a leaking water pump. leaking hoses/radiator seams or a failed head gasket.
Also be aware that the water pump is concealed under covers and may be seeping without obvious signs of coolant on below the vehicle, this issue I have seen and repaired on Toyota engines.
If no leak has been detected at this point, removal of the spark plugs and inspection of the combustion chamber and pistons is the next step as per the video. If either have little or no carbon deposits that is an indication of coolant leakage into that cylinder, which is strongly indicative of a blown head gasket or cracked cylinder head.......However......
Toyota generally designed and manufactured cylinder heads which were thicker and more robust than most other manufacturers which helped to lessen head gasket issues, but failure is nevertheless a possibility, especially if the engine has ever been overheated.
Ive done mechanical and transmission repair and rebuilding since 1972 on almost all vehicles..
@@donreinke5863 This is by far the most thorough steps and explanation I've come across. Thanks for sharing Don.
Hello AMD, every time I watch your videos I learn something new from you. You obviously were once a great mechanical 'student' and now you have become a great 'educator'. Thank you for an incredible video Professor AMD. You are to be commended! Is it AMD or is it Ahmed?
What a bizarre failure! Great diagnosis! Doing a 2014 Prius head gasket now...total milkshake in the oil pan xD
Thanks for walking through the diagnosis and problem-solving process, especially when you ended up with something unexpected!
Great dogged determination to come up with the correct diagnosis!
This is one interesting video from all the videos that I have watched from AMD! Thank God I don't have a Prius!
Well done . Outstanding investigation.
As a master tech at a NY dealership I can say I’ve seen this problem on a bunch of 2016-2017 Prius’. I believe Toyota has issued a TSB for this issue
So what makes them GO bad? Poor design? Are replacements better made?
I have a 2016 Toyota Prius that has over 240,000 mi on it. Have not seen it on that Prius holding my breath that it never happens. I have had to replace the water pump at 150,000 mi because it ended up failing on it, but other than that it's been a very reliable car
Figure out a way to monitor your engine temperature real-time with a Bluetooth diagnostic dongle or scanguage, at your mileage you may want to replace or clean your egr/exhaust gas recirculation as they coke up pretty badly by that mileage.
There was a TSB some time ago to replace that catalytic converter pipe. The coolant runs past there to accelerate heat up since the engine doesn't run under certain conditions.
My favorite episode yet , love your solution process , thanks for taking us along. 👍
Great video on proper diagnosis. I love watching you getting answers to your thoughts. Its the way scientists work. Never assuming anything. Only fact driven 🥳
Great info..! I'm sure most of us will appreciate knowing this before replacing a head gasket just to find out it didn't fix it ..! Can you imagine!
What do we tell the customer?
Thanks again for this very helpful video.
As you were diagnosing the coolant leak with all 4 cylinders clean my question became what is common to all cylinders. Did not expect a leak in the exhaust but back pressure from the EGR made sense. Good diagnostics.
AMD you're the best mechanic ever
Great video, walking us through the diagnosis. Keep going until you have an explanation for all the symptoms, and resisting the temptation to make the analysis fit the assumed cause.
I concur.
Great video, what do you think caused the catalytic convertor coolant leak? I'd love to see a follow up on this repair and an autopsy of the broken part/leak to figure out what possibly caused it. I love watching your channel Ahmed. Thank you again.
Theres a valve in the cat that redirects coolant back to the engine after heating, it leaks. You can bypass it with a tube/hose plus fittings but you lose the quicker warm up and efficiency of this system, or you replace the cat assembly with the new updated version.
@@antpart7998Do you know if you get an fault code for this valve and what is the code?
Awesome analysis and thanks for walking us through your reasoning for why this might not be a head gasket. That's definitely something that could be missed if someone would have gone immediately with the head gasket replacement.
Great video. If past warranty, you can bypass the coolant lines to the heat exchanger. One in engine compartment, or two, or underneath where the exchanger IS. Gasket Masters shows u on two videos. ALOT cheaper.
Great video
My 2010 Prius had a blown head gasket around 300k miles I was putting in head head gasket fix until it was rear ended.
I have a 2017 now and changed the coolant at 100k so it doesn’t become acidic.hoping it helps with gasket life.
Also a coworker has 2017 Prius prime and her catalytic converter had the same issue. As I was watching the video I was talking to the screen to check the exhaust system
Thank you very much for sharing your experience. One note, in case of such a significant coolant lose, the first thing I wold do is oil inspection for "milk shake". If oil is clean, its a pretty good indication on healthy head gasket. 100% agree with you on the phenomenon of the shiny pistons, probably caused by exhaust back pressure saturated in steaming coolant. Thank you sir.
AMD, these cars have a tube that goes from the caralytic converter to the EGR and the gases reburn into the chamber. In this case the coolant is going to the chamber through the tube and EGR.
That is also true. That’s why if catalytic converter on those Toyota engines gets internally destroyed the small dust and pieces get returned into it the cylinders and from there destroy the engine for short time.
When my 1999 Camry 5S-FE blew its head gasket a couple of years ago, gas bubbles were pushed through the cooling system and became visible in the reservoir.
I have a 17 Prime, was sweating for a minute lol.. Great informative video, thanks.
I’m a Kia Technician in ONTARIO. We have the same common problem in KIA NIRO. The moment I read the title, I knew what it is gonna be.
I thank-you in advance for also posting the repair video...I suspect it may be in the whelm of us DIY'ers as long as we don't have bad rusty bolts in the undercarriage area!!
This just further solidifies by documentation that you are an extraordinary diagnostician Ahmed!! Did you wind up replacing the catalytic converter and such in the leaking part?
Bought a 2013 Prius v 3 92,000 miles runs beautifully, but it has this problem Took it to a place that specializes on these cars paid $60 for the diagnostic, $2000 for head gasket replacement $300 for water pump and thermostat. Also had spark plugs replaced, after driving it around throughout the day I get home and Walla same problem, took a picture of the low level coolant and sent it to the shop that did the repairs, hopefully you’ll get back to me tomorrow.
AMD I would love to see a video on a Prius V. I have a 2015 and it's been perfect, but I would love to learn even more about the car!
I got a 15 prius with 133k miles, zero issues & runs great.
Things are not always what they seem !!! Great detection !!!
Excellent troubleshooting/diagnosing video. Thank you 😊
Very good call ccn.!! A master at work!!!
One of my favorite diagnostics videos thus far.. another was an old video from “Pine Hollow Auto Diagnostics on an Acura MDX.. and the finding was a total plot twist just like this one…
Thank you always for sharing with us.
AMD, thank you for your amazing and thorough content. Your high level of integrity and honesty is a blessing. Wishing you and your family the best!!
Hey 👋 from Kenya 🇰🇪
Great Job Ahmed.
I think this is the problem with my 4th gen prius. It started losing coolant with no visible leak and runs perfectly well. I got a fixd obd2 scanner and have it reading the coolant temp and it has been within normal range. Thank you!
Hello AMD. Thank you very much for the video. Love watching you work. Can you please do a follow up in this video with what the fix is and what parts and other things you had to do to rectify the problem and the total cost of the project. As always my prayers to you and your family and your shop and shop family. Stay safe. Peace.
Please do an internet search for T-SB-0135-19. There is a PDF that explains the repair and the coverage under different Federal and State regulatory emissions warranties.
Good job, you should be proud that you kept going and found the correct problem
This is why car owners need to find a mechanic like you. Most mechanics would have just replaced the head gasket based on the symptoms, charged the customer and sent them on their way.
Reminds me of my Buick V-6 intake Coolant leak. Took me a while to find that problem!
I had the exact same problem on a 2013 HiHy, and yes it was mysterious until it made sense! The slightly sweet smell from the coolant running into the hot exhaust is also misleading because makes you think about head gasket.
Hey Now the concern is if it overheated. If you make the repair the head gasket can go following week. You tell customer that information.
Excellent tutorial
I had no idea that coolant pass through the cat to heat it up, wow, i would totally miss somethig like that, like you've just said, white smoke , extremely clean cylinders, head gasket, and i would be wrong, thank you for a top notch class on the prius, i loved it
This need a follow-up. Interesting story
This was a great video as usual. Would have been cool to show a diagram ( if there is one) of the routing for the coolant lines thru the egr/catalitic converter.
AMD doing his best Sherlock Holmes. Great job - I hope it works out for the better for the customer.
Regards from POLAND ; Master Tech
Very interesting indeed! I love it that you take us along before actually figuring out the problem, no staged "voila" diagnosis. I can't believe the exhaust/cat is cooled also, holy crap. so envious of your critical thinking/diagnosis, that cylinder scope is invaluable. Everything you said made sense, even though the problem was not making sense. Easy to understand why many would just "jump on" the head gasket diagnosis/job. What a sinking feeling when they restarted the car after the head gasket only to note the smoke. Would be even worse if they let the customer take it only to have it return the next day with an upset customer. Don't get me wrong, we have all stumbled and made errors, but this would have been a big "ooooops" for sure.
Thanks AMD!
I’m glad that this engine isn’t a head gasket issue, but what is it with Toyota engines and blowing head gaskets?
Any chance that catalytic converter is covered by a manufacturers extended warranty for an emissions device? 10 years, 100K miles?
Good question. What to know too!
The heat exchanger IS covered under warranty if you are within the time span. If not, u can bypass the cooling lines in two ways.