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I actually don’t think there is any hope of fixing my vehicle. No codes come up.
I have changed the following parts:
New exhaust system
Fuel pump x2 Reading is 52
Brakes Good now
Calipers Good now
Rotors Good now
PCM x2
8 spark plugs
8 coil packs
Camshaft sensor
Crankshaft sensor x2
TP sensor
Oxygen Sensor
Air Charge Temp Sensor
New Battery
Fuses changed
Relays changed
Ignition starter switch
Ignition lock cylinder
Electrical wiring all checked good
Cleaned Throttle Body
There are other sensors also, but just can’t think of them.
My truck is a Dodge Ram 1500 SLT 4.7 QC. It will not start unless I put my hand over the throttle body. When it starts and I can hit the gas it will not stay running, no matter what I do under the hood or inside.
It completely dies and sometimes it will start back up and then it may take 15 tries to start it or it won’t start until a hand is placed over the TB.
Anyone know what is wrong with it? No air leaks anywhere and purrs like a kitten when it runs. Does not miss or anything, sounds like a new one. No codes.
I have had Dodge garage with 6-8 mechanics and they called in Dodge Manufacture guys, electricians and I have had friends and personal mechanics to also look at it. They have no idea what is wrong. If I run the truck on the road it will quit on me. Dodge garage said that the PCM was bad, so I replaced it a second time. Said the PCM was responding sometimes and sometimes it wasn’t
Good luck in helping me figure this out.
Who can figure this one out.
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Q: with all this money spent throwing parts at the problem, do you think you could have spent $100 for a professional mechanic to perform a diagnostic :whistle:
[quote=”Wrench Turner” post=35812]Q: with all this money spent throwing parts at the problem, do you think you could have spent $100 for a professional mechanic to perform a diagnostic :whistle:
http://www.youtube.com/watch?v=KDnivh5Odfk%5B/quote%5D
Reading the post through, it’s been to the dealership, other mechanics have looked at it and he seems to have followed the advice given at all times?
OP- is there an inertia switch on the fuel system that is designed to cut out the fuel in the event of a crash that could be playing up?
I have already had 6-8 Dodge dealer mechanics who looked at it. They kept the truck for almost a week trying to figure it out. They hooked it up multiple times and done different tests on it. They even called Dodge manufacture to get advice and called in two electricians and all wiring is good.
I have had many friends and people from parts stores who work on vehicles tell me something but it does not work.
I turn the key to start, it will turn over and hit like it wants to start and then it stops. You can do it multiple times and it might start and it might not. If it starts it runs smooth, no missing, purrs like a kitten. Runs great.
But, if it don’t start, you have to turn the key completely off then turn it back on to run. Doing this over and over until it starts.
If you take your hand and put it over the throttle body it will start every single time and run perfect.
If he takes it out on the road or hit the gas quick and hard it will die. Just holding the gas down easy it will stay running. If you rev it up easy it will run. He run the truck for two days and didn’t quit at all, he put the ATV on the back and it made him pulling a heavier load and it quit more often. If he pulled off the road, sometimes it would start back up and sometimes you would have to put your hand over the throttle body. Go until it quits again.
But it runs really good when it runs.How many miles are on the vehicle?
The ignition and engine management parts you changed, what testing did you do to confirm they were bad?
Also, some PCM’s if you replace them need to be programmed for your particular vehicle. However, 99.9% of times, PCM’s are never at fault. Did you check the power and grounds to the PCM, do any voltage drop testing or even see if you have any REF voltage on any circuits?
Reading this “turn the key to start, it will turn over and hit like it wants to start and then it stops”, does the vehicle stop cranking or does it continue to crank but no start?
[quote=”dreamer2355″ post=35995]How many miles are on the vehicle?
The ignition and engine management parts you changed, what testing did you do to confirm they were bad?
Also, some PCM’s if you replace them need to be programmed for your particular vehicle. However, 99.9% of times, PCM’s are never at fault. Did you check the power and grounds to the PCM, do any voltage drop testing or even see if you have any REF voltage on any circuits?
Reading this “turn the key to start, it will turn over and hit like it wants to start and then it stops”, does the vehicle stop cranking or does it continue to crank but no start?
The key is in off position, turn key to run and it will hit the first turnover and then it will die. It does not continue to crank. Have to turn the switch in the off position then turn it back to run and it will hit again and die. The key has to be turned completely in the off position after trying to start it one time unless it starts.
We have tried to turn the switch on and try to start it hits the first time and tried to crank it again without turning it off and it won’t do anything at all. Have to turn it to the off position every time to try and start it.
I did no testing on the parts we changed, I was just changing anything that had anything to do with making the truck run. Approx..120,000 miles on the truck. The truck was checked by certified mechanics after we replaced the parts and everything came back good. No codes, no wires grounded, no breaks.
The mechanics and Dodge manufacture blamed the PCM, because they had never heard of it. It has been changed 2 times and there is no change in whats happening. Both were programmed with the truck. The truck starts fine if you hold your hand over the throttle body and you couldn’t ask for a better running truck, no missing or anything. When we keep trying over and over to start it, you can tell there is gas build-up through the exhaust.
I really appreciate you all trying to help me. I have three people wanting to buy the thing, but I can’t let it go, not just yet.In your post you mentioned changing the fuel pump ( twice , I beleive ) what brand pump was installed ?
you mentioned 52 psi of fuel pressure. I will assume this is while running. did you do a fuel pressure check with the key on but not cranking ? with the vehicle running and fuel pressure guage hooked up turn off engine and watch the pressure. see if it drops quickly. it should hold ( or drop slightly )
try this – if it cranks but wont start. turn key off then back to on ( but not to crank ) then off and repeat ( 3 times ) then immediatly try to start. if it fires up I would say bad fuel pump. if the pressure guage drops immediatly after running this would indicate a bad pressure regulator ( part of the pump ) I ask about the brand of the pump because if you installed an airtex pump this may be the prob as these are well known for a high rate of failure.
This would be a good one to show us on a youtube video exactly what you are doing when you put your hand on the throttle body. intermittent problems have to be the most difficult because you can’t rely on diagnostics if the testing is done when the car is working at the time of the test. I would love to see Eric and Paul together sink their teeth into this problem. Not easy.
Nope it won’t turn over. Have to put it back in the off position and then turn the key back to run to try again.
It is OE but can’t remember the name right off, and We tried that. Still don’t work. It is pumping 52 while running and was steady. Can’t remember the other, but I was told it was good pump and good pressure. That was also checked at the Dodge garage.
[quote=”spelunkerd” post=36033]This would be a good one to show us on a youtube video exactly what you are doing when you put your hand on the throttle body. intermittent problems have to be the most difficult because you can’t rely on diagnostics if the testing is done when the car is working at the time of the test. I would love to see Eric and Paul together sink their teeth into this problem. Not easy.[/quote]
That is a great idea. We can do that, just not tonight. lol That way you guys can see what it does and how it sounds. I will try to get him out there tomorrow morning to do that if it is not to cold. WV here and it has been a rough couple of days. Many still not having power, heat, etc….
[quote=”dreamer2355″ post=36017]When the vehicle stops cranking, do you have voltage to the ignition terminal on the starter?[/quote]
Nope
You will need to look at a wiring diagram and see how power is fed to the S terminal of the starter when the ignition key is turned to RUN.
You may have an issue with the electrical portion of the ignition switch if you are indeed loosing power to that starter solenoid terminal.
A couple of things come to mind reading through this thread. The first is that if you hold your hand over the throttle body it will start each time. This says to me that perhaps the IAC is not in the correct position allowing too much air into the engine while you crank, when you choke off the air it starts. Also the fact that it runs fine when it does run would indicate that the IAC IS working which would mean you probably have a control unit issue. Since the computer has been replaced twice and the wiring apparently has been verified there is one more clue to this that has me thinking. I’m a little confused at how the engine will crank and suddenly stop. If you put this together with what’s happening when you put your hand over the throttle body and it does start I’m left wondering if you have an ignition switch problem. If the ignition switch doesn’t send a signal to the computer to set the IAC the IAC will not set. Also if the ignition switch does not send a signal to the starter or that signal is interrupted then the starter will stop cranking midway. If it were me I’d be verifying the operation of the ignition switch to see if it’s sending out the signals it should.
Keep us posted.
[quote=”Wrench Turner” post=35812]Q: with all this money spent throwing parts at the problem, do you think you could have spent $100 for a professional mechanic to perform a diagnostic :whistle:
http://www.youtube.com/watch?v=KDnivh5Odfk%5B/quote%5D
We are here to help people NOT make fun of their situations. If you read the post this vehicle has been looked at by professionals that have failed to produce results up to this point.
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