Misfire quick tests (what is causing it?)
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- Опубліковано 7 лют 2025
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Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.
2004 plastic part? It was ready to break you were just the lucky contestant! Great info Paul! Thanks.
🤣🤣🤣🤣🤣🤣🤣
If it breaks, it needed fixing.
I can not even say, how grateful I am for your channel. Thanks to you, I have been able to buy a lot of equipment and build my own oscilloscope (even battery powered ). I have repaired completely my BMW and repaired a lot of cars since then. Saved my family and friens a ton of money :) I am just doing this for fun, but thanks to you. Good job!!!! Cheers from Czech Republic!
Yes, BMW makes owner good mechanic 😂😅
This was awesome.. I just bought a non running 1973 SAAB.. it now RUNS!! Huge thanks for your help 😀
You are more than a teacher, you are a gift from heaven. I believe that who taught me a letter. I owe him much.
Thank you brother. All glory to God
These working diagnostic problems are great. You present the problem in such a way that it allows me to pause the video and consider what I'd do next. I like to think I'd get the diagnosis, eventually. Consistently, you show a quicker method, and the way you discuss diagnostic options is gold.
Quick and dirty works too! Thanks again Paul for posting.
Simple, real world auto repair basics!
1) fix things for your friends and family!
2) make sure that your friends and family can help you. A plumber, a roofer, an IRS investigator!
3) DONT BREAK STUFF!!
Even if you can master these minor points, it won't guarantee your success at being a repair technician!! But, SCANNERDANNER will, if you listen!!!
Thank you for posting videos, Danner. Bless your heart.
I swear that’s a design flaw of that truck I had the exact same one go bad on the one I owned. I think that seal that runs under the hood leaks on them. The spark plug hole was filled with water in mine. Great vid your the best mechanic channel on you tube!👍
This is why it's so much fun working on cars. Mr. Murphy is always there! "whatever can go wrong, will!"
You were right. That should not have broken off. But this is what can happen with plastic parts!
Paul your son is really lucky to have the chance to work together, I wish I could have the same chance with my dad, he is great thank GOD he just live in another country. GOD bless you guys
I'm blessed to have him with me!
All I want to add is thank you so much Paul for your videos, you have not idea how much you’ve helped me to improve my skills working on cars 👍🙏
Thanks for all you do. The best channel hands down for quick and detailed diagnostic work. I have learned so much from you in just the few months I've been following. Wish I had found this channel years ago. I will be subscribing to your premium channel asap. I have worked on autos and electronics for most of my life and I learn something from almost every video you have. I've told everyone except my competition about you. Haha
Thanks so much man. Means a lot
you are a awesome. Technician diving in diagnosing figuring it out awesomely. Presenting the case study. Thank you again, scanner Danner be blessed.
Haha love the vidz and joy you take in the work!
The way you are able to deduce the problem area, part, or wiring is genius! I will keep watching to find new tricks.
I am a DIY mechanic who started to learn the super simple basics at 3 from my dad. Since then I have built up a solid tool base, replaced 1 engine that siezed, 2 trans throwout bearings plus the fork, 1 bad trans, many bearings and lots of basic fixes/ routine maintenance jobs for friends.
Tools and basic knowledge have paid for themselves a 1000% over!
Thank you! Glad you're here
I enjoy watching videos it improves my diagnostic skills as Tech.
There's too many mechanics who aren't honest. Thanks for being one that is...By the way, Stephen Cox mentioned you. New subscriber!
Yeah that’s why I checked him out too. New subscriber!
Scanner Danner, I had a dodge been sitting for 3 years. I tried squirting flammables in engine, no attempt to fire. I pulled a plug. Fouled. I changed the plugs, Now it tries to start on flammables. Fuel pump bad. changed fuel pump. Now i had pressure. Still wont fire. I did an injector pattern on scope, No pintle hump, checked another, Still no pintle hump. I diagnosed 8 stuck shut injectors. Pulled all 8 and sure enough, all stuck with gelled fuel. I cleaned and freed injectors, Bad fuel rail (2004 dodge hemi 5.7 ram). Waiting on fuel rail. Again, truck was sitting 3 years. Just started this job with this company. Diagnostically speaking i had 2 hours in diagnostics. The rest is just repairs. This was a blank check make it live again job. Point is much of this i learned from your channel over the years.
That's awesome man, thank you! Be sure to flush that gas tank too!
@@ScannerDannerabsolutely did. It was nasty.
Good video Paul and Caleb. Keep them coming. Even the simple ones have great info. The both of you have a great day. Old brittle plastic can ruin a good day ❤️
Thanks for good knowledge Mr Danner your brother from sudan
me too! watching your videos all the time
All respect for your efforts this is the best channel
I appreciate that!
Easy peezy. I like quick and easy diags like this one. I'm still developing my diag skills, but learning this one early on. Thanks for teaching those who don't know. 👍👍
I'm enjoy your videos and the way you explain things so thoroughly, but I would like to see more videos using more basic tools for diagnostic.
I purchased your book and found it to be far superior to a manufacture's manual. Lots of room on the pages for notes too, well thanks for writing your best work Paul!!
Thank you Jake!
Nice of GM to put that PCV nipple in such a way that it's guaranteed to bust upon removal at any time after year 5 ...
I just did this on a Jaguar S-Type I worked on in my 2nd to last vid. Worked like a charm! New coil, and no more miss - replaced with confidence that it WILL fix the problem. Learned that from you about 3 years ago! 👍👍
Quick and easy, "git er done!"
The rest of the testing is great to show what "could be" needed.
Thank you for posting this video. Every time I watch your videos I learn something. Thanks again.
scanner danner
the international teacher of automotive diagnosis
Kids these days just don't understand . your a good guy teaching these things
I stopped gluing plastic. There are a number of Plastic welders (cute soldering irons) with metal screens would make a break stronger than the rest of it Bye the way, I got your book a number of years ago, it is amazing.
Thank you so much!
Nice to Have you bro, you are really Equipping us with Knowledge
It was probably cracked before you got there. Good ol swapnostics. Thanks for sharing!
Thanks Luke.....you all are bunch of talented people...teaching us....Salute...
I just had this issue with my wife's Buick Rainier. I grabbed a few from the parts garden.
I 💘 love scanner danners life lesson's !!
Paul, great quick write up using process of elimination troubleshooting. Also, thank you for not editing out , " oops " , moment when you break the plastic on the intake housing. That happens all the time, it seems, on cars older than 7 years. Please create an Amazon link to your favorite epoxy combo so I can support your channel. I already bought your e-book. Thank you for creating content for the diy as well as young technicians. Peace.
I had a similar issue recently, thought I'd "ScannerDanner this diagnosis", went big in my diagnosis and didn't determine a significant fault (even with my Danner For Idiots Manual at my side). Sent it out, naturally it came back but experience was on the shop floor this time- no diagnosis other than a quick scan and my previous diagnosis, 45 minutes later, coils were moved, plugs were changed and an injector was going in. I knew straight away I had dug too deep in my diagnosis but was consumed in finding the exact fault. Sometimes it pays to keep it simple.
Have learned a ton from watching your vids. Thank you for that. Seems the broken plastic happens to all of us sooner of later. Quick tip use soldering iron to melt the plastic back together and create something for the epoxy to hold onto then use the epoxy. Havnt had much luck with just epoxy by itself. But definitely strengthens the bond when using iron first. Keep up the good work you do there im sur e we will learn lots more from you.
You are the best fault detective
Genuinely enjoy what you all do,good onya cobba
Pretty standard to change all plugs too, if they have been in service for a while. Good video.
Thank you, you are my best teacher
(From Saudi Arabia) 💙
When you were fishing for your son to say the next step is check/move the spark plug I kept repeating it 😂😝
As always, excellent content Paul!
Great video. You explain things way better and easier than my instructor. I'm learning more info off UA-cam than In my Auto Class. 🤣🤣. Thanks for the video
Thank you! Appreciate the comment. I'm a teacher too 😉
I always appreciate the time and effort you put in making these videos... thanks guys
Thanks 👍 for sharing your knowledge to the world. This is American. God bless.
Thanks Luke, Caleb and Paul.
Paul,
Great video, diagnosis, and fix - thank you! Wow those coils are not cheap!
God bless to you and Caleb
Paul
Quick and dirty works bro. Nice!
Thanks for your time and effort educating people. I watched so many your vids and learned a lot after all. Merci! Cheers)
Thanks, Paul! And Caleb! Hope your JB Weld fix went smoothly! Love your channel, brother.
Lol it did!
ScannerDanner hahaha I commented before I saw the end of the video 😂
Thanks for posting Paul. Recently i replaced the left hand heater hose on a 04 envoy. Had to remove the transmission for that...GM engineers are insane..ridiculous.
🤣🤣🤣🤣🤣🤣🤣
Holycow, all that for a hose!
@3 name changes allowed every 90 days. YES, been there, done that.
The adventures of Javier 86 lame
I have to replace heater mixer shaft on my 2002 Ford utility to replace a part worth $80 requires the removal of the whole dashboard the quote from the Ford dealer is $1,300
u are a car guru scanner danner thumps up❤
SD - You are a GREAT INSTRUCTOR - thanks for ALL you teach and share 👍 It is true that one can always make some good , easy checks without an oscilloscope and analyzing waveforms 😏 but still , as in this video , you used a diagnostic analyzer which has the ability to read live engine data ( not just a basic / cheap code reader ), to see that the miss was originating from cylinder three ( misfire counts )- if you did not use a diagnostic analyzer with the ability to read live engine data - you would not have readily known which cylinder was causing the miss. Ha Ha - not stating anything you don’t already know as you are surely a master auto technician - but mention the difference between a code reader and a diagnostic analyzer - because a good diagnostic analyzer which can read live engine date will cost more $$$$ . ✌️✌️
If you don’t have the ability to see the miss with your code reader and you have a dead miss with a code for a cylinder you can still swap the coil and or spark plug and see if the code is back on the same or different cylinder
Awesome easy diag! Exact same thing I would have done....the plastic breaking just falls under, well darn! Old brittle plastic....(as the other comment said) you just happened to be the un-lucky contestant.... we've all been there done that...
Simple and effective. Great video Mr. Danner.
I just had a fun time finding a misfire on my 3.3 caravan. I was not close to my tool box and equipment but at home with only a cheap scan tool and a small amount of tools.
It had a #3 misfire. removed the plug wire at the coil pack and had a very weak spark. I replaced the coil pack and 4 days later it started to miss again. This time it was on #5. Since the plugs and wires only had 45000 on them i didn't suspect an issue. The wire had spark and plug looked perfect. I switched the plug with #6 and even though it still missed on acceleration it would not set a code. Then i remembered that stupid Chrysler has to see a misfire for 2 drive cycles before it will set a fault code. The miss was now on #6.
To make a longer story short I learned a lesson i should have remembered from years ago. Don't even use Champion spark plugs in your yard equipment. It's a good thing that we don't have hair as we would have pulled it out by now.
Hilarious! I knew you were going to break that housing not remembering that 90° elbow on it. Good stuff.
Awesome video Paul.. Nice, basic, and straight to the point.. It wouldn't be right if something doesn't break while you are working to fix something else and all u did was breath on it then it snaps in two lol... Another great video brother thanks for sharing
This is not easy job if don't have scan tools ,thanks for sharing
Or jist do a quick rpm drop test and unplug each coil one at a time to find where the misfire is at then swap coils. Still pretty simple
Can do it on quite a few vehicles just by feeling exhaust header/manifold temperature from cold startup. No electronics needed. Some manifolds are buried, and make this difficult, however. Scan tool is definitely the easier way these days.
Again very good and interesting
Plastic parts when they age, can become very brittle that's what's have found through the years.
Good to know that compression test. I swapped around my coils, plugs, injectors, it stayed on 3. Eventually I got a code for intake leak, but that was long after the misfire started. Never did find the leak, got a cheap fogger setup and everything too. Makes me want to go electric
Next step if it stays in cyl3 is check power and grounds to cyl3, then the sparkplugs. Mouse might have chewed a wire off it. If p&g and plugs are good, I'd go after the injector, first with the screwdriver trick to hear if it's clicking, then power and grounds.
Have to be careful though, some ECMs will shut an injector down when they detect a misfire to try and save the Cat.
CO Jones I would just scope the injector it’s fast and more accurate but that’s a good truck to just don’t know if injector is sending the right fuel pulse to the hole
📷 man thank you👍 👋 👋
KNOWLEDGEABLE Sir ScannerDanner
Thank you 👍 Take care 👍
Sir ScannerDanner
From Nick Ayivor from London England UK 🇬🇧
Could you recommend Permatex plastic weld as being any good. There's a lot of plastic in circulation and it's very useful to know just what will do a permanent fix without trying every glue on the market? Low tech fix on the misfire worked a treat. Great backup team on the camera side. Everyone sounds happy and healthy. D. G.
Not sure, I just used what I had
Just got a flash C.E.L. PO300 on my 2017 RAM 2500 6.4L 80K miles. Light didn't stay on, but starts and runs smooth. DTC's:
PO138
PO0152
PO158
P1621
P1622
Good man may God bless him
Smart and simple !
Nice one 👍🏼 !!
199K subscribers. You're almost at 200K! Congratulations! Keep up the good work, I am happy for you!
Great info! straight to the point, at the end of the day time = money
Very good brother Danner. Boby from P R
Great in-field troubleshooting.
Thank you for sharing Mr. Danner. Two Thumbs Up
Nice job Paul....
Another amazing video from the Master!
A nice and simple 'back to basics' video 👍
This is why i hate engineers, every day i see more and more structural parts going from metal to brittle short lived plastic fitting/housings.
Valve covers, breather tube assembly, vacuum hose fittings, PCV pipe, door actuator gears, radiator fabs that shrapnel, coolant thermostat housing, timing chain cover, timing chain guide, even a throttle body housing. All these parts i listed used to be metal, mainly aluminums or other alloys.
The valve covers is one that definitely kills me the most.
Keep up the great work Paul and Caleb
If engineers had any say in this, they would have designed a car than never breaks, period. But nobody could afford it.
The problem is you are greedy - you want your shit to do everything, but you don't want to pay for it. This is the result.
Quick and easy! 👍 Thanks Paul!
My first test on suspect ingnition missfires. And yes the plug is next. Let the PCM help you test!
hate old plactic that stuff u used is a life saver.nice vid.
Very good repairs, Danner Greetings to your magnificent partner CALEB. from Tijuana Mexico 🇲🇽
Paul. Did about the same broke off a plastic nipple used J B WELD AND BAKING SODA. HAS LASTED 2 years and running
Great video again Paul & Caleb, thanks for share.
Hi Luke! I appreciate the website!
So much passion, thank you
Thanks Luke
Thank you Paul! you make this so easy!
Good job.
I just did a truck just like that and did it the same way!! Dead miss on 5 moved it to 2 and the miss moved to cyl 2... BUT I recommend changing the spark plugs as well as that coil...
Yur way if it moves u cant actually if it's the plug or coil, one step at a time bro.
good video scanner danner to fix misfire
The airbox repair took you longer than the original problem LOL!!!! It happens sometimes.
And a few weeks from now he needs yet another ignition coil.
When you say higher milage, if spark plugs at 120+k change them and all the coil packs. Save good coil packs for backups in an emergency. This is just to me routine maintenance.
It is a friend, so we will do them then. These are not cheap and he has 4 little kids :-)
ScannerDanner well At a minimum, I would advise him to buy 2 and not just 1. And then to buy more as soon as he can financially afford until he has 6 new ones. And then to keep very good records as to which was replaced when (date and milage with cyl number replaced).
As you know as well as many of us once one goes, it is not long before another and another goes bad!
Wisest advice is to replace all at the same time as all have the same wear. Next best advice is to have a spare on hand as the next failure is likely to be soon!
Your the man Danner
Thanks, we must check easy test first.
I would have swapped the cyl 3 and cyl 2 coils, and also swap the cyl 3 plug with cyl 4. If the misfire goes to cyl 2 like yours did, it's the coil. If it moves to cyl 4, it's the spark plug. Rule out both the coil and the plug at the same time.
9 times of 10, you'll find high mileage and it's guaranteed nobody ever changed the plugs, if they did it was cheapest copper ones and that was 40k+ ago... after they waited for the original 100K "lie" plugs to hit 80k+
Ergo probably fuel injector.. did this last weekend.
Times I see garages change just coils due to failure/misfires and leave old plugs in place with rounded off electrodes (well worn) and gaps you could walk through , causing hotter running or overheating to the coil driver/logic circuit long term , half a job in my opinion, no surprise that Mr Danner suggests if in doubt ditch those used/worn plugs too, logic coil life or separate driver coils can often be prolonged with plugs changed periodically or on time
I always check and see if the coil pack looks like it's arcing out the side. If so, you can wrap it up with some electric tape to get by.
I most times swap not only the coil, but I also swap the plug. Say I have cyl number 2 miss on a 3.5l honda. I'll take the no. 2 coil and put it on no.4 cylinder and no.2 plug in cyl no.3. I do this to cut on time duble wotk. But yeah. It's usually a coil.
Had that same issues with my legacy turbo couple of years ago,also broke the nipple from the airbox.finding one was pretty depressing :)
Great tip, this is a great diagnostic, See it a lot.