Part 2. GM no start no fuel troubleshooting "Oil pressure switch"
Вставка
- Опубліковано 25 сер 2024
- visit me @
toolsandtime.com
Part 2. In this video i give an example of one way i go about trouble shooting a no start issue when i have limited resources. on a 95 Chevy Tahoe
We will be looking at the oil pressure switch side of the circuit This isn't how I usually go about it however I wanted to give an example of what you can do with just the basic tools and schematics to trouble shoot a no start issue hope you enjoy
I realize this video was made over 10 years ago but I just wanted you to know that is still helping people today, so Thank you, Will. I have an 89 GMC Sierra SLE 5.7 TBI and have been struggling with a crank no start issue for a long time and no matter how many mechanics I have asked, unless you find one of the old school Shadetree mechanics that doesn't need to hook a vehicle to your computer do you know how to fix it, not one of them knew the answer because of the age of the truck. Your 2 videos on this topic, even though the truck is a newer year model, was the first that help me realized it could be the Fuel Pressure Oil Pressure Switch, which I have since learned differs from year models of GM trucks. ♦Please note for anyone dealing with the same problem please pay attention that it does matter what year model your truck is as to how many pins are in the fuel pressure oil pressure switch, 1988 - 90 will have only 2 pins in the switch, 92-95 may have 2 or 3 and 95 - 99 will have 3 Pins.♦Also, pay close attention that in other videos it may be referred to as a Fuel Pressure Sender which may be accurate in newer 3-Pin models, however in 1988 to 90 Fuel Sender is a separate component/part, in a different location, it is located on the Driver side lower engine block on year models 1988 to 90 and differs from year models 91 to 95 and 95 to 99 where the switch and sender maybe integrated. Video part two was extremely helpful in showing how to bench test a part to show how it works. 🔶Other than discovering this switch could be the issue for I no start, I have also discovered that is very important on your models 88 to 90 as well as 91 to 95 to inspect the braided body ground straps to the engine block. As well as the ground wires to the ECM and fuel pump relay which are black, black/white stripe together and a 2nd set that is a black wire & a tan with white stripe are ground wires that on 1988 to 92 models are typically grounded to the engine block on or near the thermostat housing(bolt)and can become loose over the years from vibration or corroded causing a faulty ground, which I stumble upon by learning from videos regarding testing for proper ground and voltage with a Non-Led test light. As it turns out when I tested where those grounds are mounted it showed a very weak or dim test light, so I jumped it to another ground on the engine block which had a very solid bright light, went to start the engine and was very shocked that it fired right up, all it was was a weak ground connection at the bolt where the ground wires were mounted to the thermostat housing. So if you're having this issue and have this year model of truck, hopefully I can save you a lot of time by checking this and all of your body ground wires to make sure they have clean, tight & proper connection.🔶 When you own one of these year models of trucks it can be very discouraging and frustrating to find out that many younger generation mechanics do not know how to work on them or even care to learn how, even though they are very plain and simple and more basic to work on the newer computerized versions where you just plug it into a computer and it tells you where to start putting parts in it to try to fix it, but don't give up keep searching & trying and you will find the answer.❗🙏I have much appreciation and gratitude to mechanics like Will and others who are old school or enthusiastic enough to learn in order to teach and post instructional videos on UA-cam to help us out with our old classic GM trucks. Thank You All‼
This is awesome to hear
Man oh man, this dude is the bomb instructor!! All kidding aside, I really like how he fully explains each detail and even reviews and bench tested the old and new components in detail. This is the first time in my life I ever thought enough about anyone on here to consider giving a positive comment but Robinson you are deserving and the best instructor I have seen on youtube hands down!!! Thanks Bro and I will be telling everyone about "robinsonsauto"...
you are the honest face that everyone wants to see in a car mechanic....your video is a lot of help ...thanks a lot
I watched both videos and it was my first encounter with your channel. What a great day today is, finding YOU!! Man I just read and liked about 10 comments below & couldn't agree more with EVERY one!!! You SIR ARE an AWESOME mechanic!!! Thank you! I'm troubleshooting a 1987 Camaro 2.8 & feel confident with the info, I learned from you!
Agreed. Man of integrity I'm sure .
I'm willing to bet he's even honest and gives his customers a fair price with a good repair. In fact I'd be going to bed he almost under charges on most jobs. He is worth whatever he may charge and then some .
This 11 year old video helped me fix my truck after replacing the fuel pump and having intermittent issues. Thanks
That’s great to hear
I don't mind even watching the ads because I actually want this guy to make money 😊
Thank you for your support! It means a lot to me.
Probably the best video explaining the fuel pump relay no start related issue. Thanks for posting.
After watching the two videos in this no-start series, you can work on my vehicle any time. Excellent explanation and logic.
I just wanted to share a special thank you for this two part video. I've had an ongoing issue with my 98 Silverado similar to the one in this video. My truck would fail to start on humid/rainy days. Following your videos, I found a cracked oil pressure switch, which was shutting off my fuel pump immediately after starting. The humidity was shorting the sensor. Thank you, thank you, thank you!
If my fuel pump isn’t running at all this could be my issue?
Your video helped me repair my 1999 Yukon ,oil switch ,tapped it vehicle started ,pulled relay shut off .Sir you saved me from dropping gas tank and replacing fuel pump ,thank you
Your 2 part video was great help for me to troubleshoot this problem. since I had already replaced fuel filter to no avail. due to circumstances similar to ones in your videos I'm almost positive this will fix my problems on my 2000 Tahoe. Thank you immensely...
If you ever think of retiring, you could be THE BEST automotive Teacher High School, College, Major Automotive company Senior Instructor,........ You absolutely know your stuff, are humble about it and you have that magic that allows you to make it so that others can understand and learn from you. Not using your shop tools and using what a typical home garage guy would have is beyond helpful!
You are The Man! Thank you!
also wanted to add, I agree, if I were to leave it be with just replacing the relay chances are it would be fine for many years, however in that rare case the relay were to fail again, as long as there is oil pressure the "back up" pressure switch will keep you in operation. what you will experiences is longer cranking times with a failed relay and an operational pressure switch due to the fact pressure needs to be obtained to close the contacts...
It’s simply just a backup, Hope that helps
Great job man, also in your honor I too am going to start calling it continudity. Keep up the good work
You noticed that too huh? Lol 👍
Had the very same problem, '96 Chevy C1500, instructions on both videos were spot on and understandable. Thank you very much.
Thanks for the tip on oil pressure switch causing my fuel problems. Been a month trying to figure out why no power under load. Put the switch in and now feels like a new vehicle. Thanks!!
Other videos on GM fuel pump relays don't mention anything about the effect of the oil pressure switch on the fuel pump relay, thanks for helping me fix my problem. That little demo where you remove and re-install the fuel pump relay really helped.
Dear i have captiva when on key automatic not start fuel pump and wont start what i do
Did your oil pressure gauge show oil pressure even though oil pressure switch was faulty?
Great video. Took my new to me 2005 coach with a 8.1 liter workhorse chassis. First trip broke down twice (not related to this issue). Got home and never was able to start again. Two weeks later, I have already dropped the fuel tank and the pulled the fuel pump. Tried to start and no go. I ran across your video and decided to pull the oil pressure sensor. I did your test to the pressure sensor and son of a beach!!!! That was it. Thanks bud.
YOU ARE THE MAN!!!! please never stop making your video's you are helping so many people. THANK YOU!
A hero, so cool and confident. A good mechanic is like a musician, so talented.
The two videos about the GM no fuel trouble shooting were spot on and very easy to understand.
One of Americas top mechanics here, thank you for the great videos on how to properly troubleshoot!
Thank you. I watched both videos. I am in the process of trouble shooting my 1989 Chevrolet Beretta no start. I replaced the fuel pump in the tank, and got the car running. Then I replaced the signal switch as the left side would not blink, and got the signals working. But then I could not get the car to start again. I have ordered a $30 fuel relay switch and hope that will get this 33 year old car running. It has been in the garden or garage since 2005, running it twice annually. We ordered it new in 1989.
thanks, i could of let it go with just replacing the relay it ran and started fine, however i just wanted to double check the system. glad i did
Thank you for an excellant tutorial. I want to add this feature to my son in laws car that he switched from mechanical to electric inline fuel pump. For safety shut off fuel when vehicle is upside down, perish the thought. And also to leave pump off when key on engine off. It's carburated so it will start ok then oil pressure will quickly bring the fuel pump on. I thought of a 3 wire oil pressure switch but didn't remember the details. You completely educated me on this switch. And can even do an electric oil pressure guage now.. Not wild about the oil tube type of gauge on it now. Leaks under dashboard potential and a leak under the hood spraying oil around "not cool" either.
Will you are the best!!! You are so easy to follow and learn from. Thanks. I appreciate the comment from Dean Studer on fire safety and rollover protection. Now I have identified my no start. My 2001 S10 cranks, good spark, good prime, no start. Bad wire harness to the oil pressure switch. I found that after I replaced the intake gaskets, I had a no start. The 3 wire harness to the oil pressure switch broke because of age, heat, and movement on the gasket repair.
Nice job buddy. Great explanation, good easy listen and you shoot it straight. New fan!
Thank you O so much. I watched all sorts of other videos non clever come close to your most easily explained educational video, Thanks again
These two videos are the first time I watched you and I had no choice but to subscribe. Well done sir. You are a good mechanic as well as a youtuber
Excellent fuel pump relay diagnostic on GM . Basic common sense diagnostic video and commentary anyone can understand. Thank you Robinson auto for saving me time and money. Life is good !
Ironic that the back-up switch for the relay also went bad and left the truck stranded anyway haha. Way to go the extra mile and make sure all the components work as they should! Very clear explanation of the process as well. Right on par with ScannerDanner :)
I was under the impression that it was only OBD 2 that had this circuit.
I had an occasional intermittent cold crank , no start on my 1991 305. I found the oil pressure gauge was not operating properly but once it does start it never fails to restart once hot.
I replaced the oil pressure switch & the the cold no start problem returned. I'm in the process of checking all grounds & fusible links now.
Now this video is the best diagnostic of an Oil Pressure Switch that I've seen. I want to thank you for inspiring me to fix my friend 00 Pontiac Sunfire. It's easy to comprehend and I absolutely like the colored wiring diagram. I'm a new subscriber now and I highly recommend other folks do to!
Excellent moving chart and description. You have so much potential and already so much knowledge. Thank you for this video. You made me $120 today. I really really needed it too. Thank you again!
My 96 c1500 sat for 8 years. Gonna watch more of your videos to get an idea of why it isn't getting fuel. Thanks
Great video set (part 1 & 2). I watched another one before yours and was lost. You speak in easy to understand terms, and it's obvious you are not trying to wow people with your brain power like that other one I watched. I completely understood every single thing you were doing and why you were doing it.
I just want to say thanks for the 2 videos here on this and walking through the troubleshooting process. I have a 1990 olds cutlass ciera that kept shutting off on me. I walked through it an verified all the components were fine. fuel pump, relay, and I had spark. Ended up being a fuseable link by the starter, go figure. Thanks a lot!! great walk through.
Man im trying, took a little break this week. put allot of time and effort in the channel and website this past year... im surprised you don't get more hits man i been hooked spent a few hours last night checking out your vids, very impressed
Awesome on first fix and to find the second helping the customer not to get stranded
If already asked and answered, I apologize. My understanding is the oil pressure switch isn't for a backup. The relay in the box when powered works for 10 seconds allowing a start and oil pressure to build. Then the oil pressure switch takes over and the one in the box times out and stays off until the next time you turn the ignition on.
Now, the reason I understand all of this is from watching your video and having the "a ha!" moment. Nice work.
There is only one word to describe this presentation. " E X E C E L L E N T " !
Sir, you just saved me a pile of money on my 1994 Silverado. But a relay and he fired right up. So I unplugged after watching your video. It died right out. I’ll be swinging by the parts store in the morning or the oil pressure switch.
Great extra effort. That's taking pride in what you do and taking care of the customer. A lot of technicians would just replace the relay and then when/if the new relay goes bad the customer would be stranded, again.
Nice educational video. Just bought my son a 305 throttle body firebird and it has a no start. Maybe not the same motor, but I learned something about testing the relay and oil pressure switch. Now I wish he had tested the fuel pump so I could have learned what to look for there. Maybe in the next video.
Flipping brilliant mate!!!
Power On.
Thank you for the visual on location of the pressure switch. I didn't know what it was under my distributor. Not even the manual shows the correct picture.
you can keep all the videos about 98 gm trucks coming please :)
Excellent explanation, I'm about to install and external fuel pump on my 63 gasser and this is an excellent idea to shut off my fuel pump in case the motor shuts off, blows up, or if I roll over. Once the engine turns off and loses oil pressure... it'll definitely shut off my fuel pump.. Safety issue. Thank you 😊
Great video! Can't wait to try these tests! Thank you very much!
Excellent video, you learn something every day thanks for taking your time, plus explaining with wire diagram and troubleshooting. I appreciate very much, will continue looking at other video's
on my 93' the pressure switch is not 1-1/8", its 30mm and you have to remove the distributer to get it off if its the original. Gm put these in tight and the tree is fragile and you will break it off if
you don't support it with a 15 inch adjustable wrench while using a 30mm box on the sender. Have an extra distributor gasket. mark the position of the rotor and distributor base. Its quick and easy but adds a second possibility in diagnosing any problems if it doesn't run right. I try to restrict repairs to one thing so there arnt multiple possibilities to chase if a problem.
Great video with the exact info I needed. 1997 Blazer 4.3.
You saved me!!!!!!.. this guy is the best
Wow, I learned a ton from this video. Thanks man.
Well done !! What are the odds the relay and sender would be bad. Too bad GM stopped using the back up oil pressure system on its newer engines. I wonder how many shops would have just replaced the relay ?
My man that what I'm talking about I'm in school taking notes and very thang love this video
Thank God for you taking the time for making this video this is a big help with the problem im having with my truck
Thank you, you may be correct, one thing to remember, if the relay is good that will over ride the oil switch and the vehicle will start even with no oil pressure, so yes if you do have a bad relay it will be very long crank times and my not start depending
THE OIL SWITCH WAS FOR A BACK-UP FOR A BAD RELAY not for safty!
your video was very helpful, I liked you were easy to follow without any unnecessary wasted time as so many videos are. nice job.
I know this is a pretty old video but I just want to let you know its really well done!
very helpful! specially since my wife's suburban with the same set up is doing a random no start thing. her's is a little different issue but i think what you are doing here may have given me the answer i need to get hers going. haven't checked the oil in hers and she NEVER does so it may just be low on oil now that might be why hers will only start when it's warm out (assuming because the oil expands when it's warm giving her enough pressure to start) it won't start cold early in the morning
I wish I had a cool ass mechanic like you. Great work
THANK YOU! YOU'VE EXPLAINED TECHNICAL, SO A NON... CAN UNDERSTAND!
Thank you...thank you...thank you!! been trying to pinpoint this problem for a long long time!! Very well made video. Perfectly explained
just wanted to add i mentioned this further down the comments,
some engines with excessive bearing clearances, worn oil pump, low bat. may not reach 3psi while cranking,
i can say, it did helped some. had a couple in the past with long cranking times that just needed a relay. very rare though
don't have the vehicle any longer, i will be more than happy to perform this test when i get it in for the next service,
you know your stuff man ... no code diagnose is quite hard. but you are a Pro man
Great troubleshooting. I am having similar problem with my 93 4.3. I will try this. thank you!
Well my check engine light would come on after minutes of driving, I checked all I understood, THIS is likely why my 94 k1500 Sierra died! Thanks buddy, owe ya one.
thank you, glad i got it out to you. hope you found it helpful. your more than welcome
I don't normally respond to opportunities to state my opinion online, because I do not frequent the web and/or encounter situations in which you can honestly provide "positive
feedback." Will Robinson is an exceptional mechanic and an equally impressive mentor.
I am convinced of this fact because of the level of knowledge he exhibits and the manner in which he chooses to do so. Basically, I am discouraged by online mechanics who have a vast amount of equipment at their disposal that is not readily available to me. Further,
these individuals are surrounded by a team of workers, when I generally have to complete
my vehicle repair problems alone. I remember one occasion in which I sought information
online, and this particular mechanic requested $35+ dollars to help me troubleshoot the
problem. I am accustomed to the day in which you could go to the auto dealer, and briefly
discuss your mechanic problem with one of the technicians. Now, people are trying to profit from their potentially bad advice. Will is a pleasant addition to the auto repair dilemma, and now many people won't be Lost In Space: There is no "danger Will Robinson"
because you know what you are doing.
I want to know what wiring diagram you are using. Really helps me follow along.
Good stuff! Simple explanation with simple illustrations. Thanks from a grey beard.
Very impressed with your knowledge, young man. I have an issue with my 93 Chevy Silverado K1500 ..long story short is that the truck runs normal but when it gets over 95° outside and I go for a 50 mile run with it when I shut it off, it will not restart until it cools down. Of many reasons ..replace the relay still happens. Saw this video and thinking maybe a fuel oil pressure switch functioning when it’s really hot. Your thoughts please. And yes, I’m very impressed with your videos and knowledge.
awesome..am gonna try installing a new pressure switch tomorrow and will get back. thanks again.
That last check solved my problem,great video,Thanks"
Good video, I didn't realize that there were further problems in the first vid.
Napa-permatex thread sealant w/Teflon i believe... i have a couple makes however i believe that's what i used
My first response on how the system was setup was from Mitchell provided by GM. that was their theory any how. Will it do just that depends. In some cases it may not obtain enough pressure while cranking example, low battery, bearing clearances and so on.
some engines with excessive bearing clearances, worn oil pump, low bat. may not reach 3psi while cranking,
i can say, it did helped some. had a couple in the past with long cranking times that just needed a relay. very rare though
Im curious about this. You had it running and pulled the relay and it kept d
Running after you replaced the oil pressure switch. Now I wonder if you shut it off and try to restart with the relay still removed will it start and run??
Awesome video! I learned something very important. Thank you!
Would a bad oil pressure switch cause engine misfires? I pulled my relay and the engine shuts off. 1997 Chevy Tahoe 5.7. I've been chasing a p0300 and specific cylinder misfire like p0308 but it's weird every time I take the upper plenum off and recheck everything when I put it back together the cylinder that misfires changes to a different cylinder. The most oddest thing I ever experienced. I replaced everything you can think of and cleaned up all the grounds wires. I notice the fuel pump relay doesn't energize sometimes when I test by turning the key on and off. I keep my hand on the relay and I turn the key on and I don't feel it click. Sometimes like 4 times in a row. I bought a new relay same thing. So would the oil pressure switch be causing this?
Great video, love the wiring diagram, thanks
I agree, breaking it down with the wiring diagram as well as double checking results in different ways. I have a 1995 GMC service van that I work on myself, so any repair I make needs to be done correctly and 100%. Thanks for the help.
Thank you for the great videos! I have a 1993 gmc suburban 5.7 350. My fuel relay is on the passenger firewall. Can I use these same test methods on this vehicle such as starting the vehicle and disconnecting fuel relay to see if it stays running? One of the problems I'm having is the vehicle is stalling while I'm driving it. Any help would be greatly appreciated.
Awesome video. Liked how you tested with air pressure and a regulator.
Thanks! Best teaching video and GOOD info I've had the pleasure to watch!!!!! GREAT
Another excellent video. Thanks very much. Hopefully will enable me to make some decisions following logical troubleshooting.
Very helpful. Thank you for your detailed explanations.
thank you, that would make more logical sense, however GM was just using the pressure switch as a back up for the relay, so if relay failed as long as you had oil pressure the vehicle would still run. now if relay was bad, it would take real long cranking times to start if you could build pressure cranking to close the contacts that was their"theory"
if the pressure switch were to fail or you lost oil pressure as long as the relay is good it will still turn on the fuel pump. hope that helps
You saved my day... made the job quick. Thanks!!
great work. very clear
AWESOME VIDEO! You are BRILLIANT!
Good question, i should make a video response for this one. if i showed you first hand it will make more sense. say if the motor jumped time, Broken timing chain or belt depending or more extensive damage, you will hear a deference in the way the engine cranks, when in time you can hear the the starter working harder overcoming the compression from each cylinder... mechanical problem say a broken timing chain the starter would spin much faster less load, do to the cylinders without compression
i have a1994 chevy 4x4 i put a new fuel pump thinking that was it but it wasn't i'm not getting power to the fuse power is going to the oil sending and the relay but no current on th gray wireto the fuse or to the pump. can you help out
I have 02 Suburban, starts & runs briefly then slowly dies. 15 psi fuel pressure with key on & dies off to zero. New fuel filter so I think it's the pump. Thanks for the video.
:)
I really appreciate these videos
Would a bad oil pressure switch cause the vehicle to crank no start also cause it to back fire? Any help would be greatly appreciated. Thanks for the great videos and your time.
Backfiring is usually an indication of distributor issues
Control module keeps relay energized if engine is cranking or running(control module is receiving reference pulses from ignition module) if no reference pulses, module turns off pump within 2 seconds as a back up system to relay, the oil pressure switch also activates the pump, normally open until oil pressure reaches about 4psi. if relay fails, oil pressure switch will back up, only when with pressure, cranking time will be longer if fuel pump don’t receive current until pressure is achieved
Ive watched both videos and I only have one question. On my 95 GMC Sierra when I filmed what happened on my circuit which is supposed to receive 12V for 10 seconds with the key on it goes from null to battery voltage for a split second but then stays zero. Is that likely a pcm issue or an ignition switch. The other tests in the first video it passes but its not priming long enough
very good info and bench test done.
great video dude you explain it well, and i learned something new
Thanh you robison auto, great video, as many others that I have watched, keep up the good work, cheers from Ontario ca.