Engine shuts off when truck gets warm

2001 DODGE RAM

70,000 MILES • 5.2L • V8 • 2WD • AUTOMATIC

BIGBULL70

MEMBER
3 POSTS

The truck cranks and runs fine until it reaches a temperature around 210. Once the engine gets warm, and you let off the gas, the truck will just shut off. It will immediately crank back up and as long as your foot is on the gas it will run and idle, but once you let off the gas it will go shut off again. After letting the truck sit for a several hours, it will crank and run fine again until it heats back up. Mechanics have replaced the fuel pump, mass air flow, spark plugs, plug wires, and distributor cap, and now they say they don't know what else to do to make it stop. Any help would be greatly appreciated. It cannot be that complicated.

Jul 4, 2020 at 6:31 AM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

Due to the fact that this stalls when your foot is removed from the accelerator is pointing to the idle control. On your truck you have a motor on the side of the throttle body that controls the idle. If this is faulty then it will cause what you are seeing. Normally it doesn't wait until the engine is hot but clearly your PCM is seeing something after it is hot that it does not like at idle and it is causing the engine to stall out unless you keep the throttle open.

I would start with this and go from there. Thanks

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Jul 4, 2020 at 11:22 AM

BIGBULL70

MEMBER
3 POSTS

Changed idle air today. Drove truck and still shuts off when the engine warms to 210.

Jul 6, 2020 at 4:34 AM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

Does this do this every time no matter what?

Also do you have a scan tool that we can monitor live data so we can look at sensor information?

Jul 6, 2020 at 12:36 PM

BIGBULL70

MEMBER
3 POSTS

Yes, on every time and no we do not have a scanner of any kind. The check engine light hasn't came on. It's really frustrating.

Jul 6, 2020 at 12:48 PM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

This could be a crank sensor issue. It doesn't fit because if a crank sensor fails, you would not be able to keep it alive by holding the accelerator. Nor does it normally fire right back up.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

I would suggest the next thing we do is monitor fuel pressure and make sure that is correct. Just because the pump was replaced doesn't mean the pressure is correct. So I would start there and then we can move on because after that we need to suspect the PCM itself.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

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Jul 7, 2020 at 12:37 PM

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