2011 ram 1500 5.7 Hemi: At operating temp it dies randomly when idle.

[Chaulky_Nope]

I have a 2011 ram that I bought with a bad motor. I swapped out the original 5.7 with a 2012 5.7 rebuilt from the bottom up. Went in with no issue. Recently it’s been dying when I come to a stop. It only happens when the engine is at operating temperature. When I start it up in the morning it drives perfectly fine.

If I drive it for a while it will drop rpm’s quickly and come right back up again, almost like a stutter or something. If I put it in neutral and keep the rpm’s around 1k it won’t die. Only dies at idle speed when it’s warmed up.

There are no codes or check engine lights. I’ve replaced the following: ecu, engine/transmission wiring harness, Vvt solenoid, cam shaft pos sensor, crankshaft pos sensor, transmission solenoids, and a few other things.

Anyone know of where I should look for a problem like this? TIPM? I’m out of ideas. Something with my transmission maybe?

 

[jws123]

clean your throttle body

 

[Chaulky_Nope]

Throttle body is brand brew

 

[Wild one]

Throttle body is brand brew

Let me guess,it's an aftermarket throttle body.

 

[Chaulky_Nope]

Nope, genuine replacement

 

[Burla]

Same with cam sensor, OEM? I seriously doubt TIPM, what is coolant temp when shuts down? Air tube clear from wheel well to filter? No obstruction like a rag? Could be air or fuel my guess. Maybe a gasket with some vacuum? Just brainstorming.

 

[Chaulky_Nope]

Yes sir, oem replacement. I’ll have to check the coolant temp with a scanner but the gage for temp is normal on the dash. I appreciate any and all suggestions, I’m at the end of my rope with this issue so I’ll try anything at this point.

 

[Ken226]

Do you have a fuel pressure gauge? Perhaps see if you can monitor the fuel pressure while the stumbling occurs.

Maybe the fuel pump or fuel pressure regulator is on its way out, and starts having trouble maintaining pressure when it's hot.

 

[Chaulky_Nope]

I don’t but I know someone with hp tuners I might be able to have him monitor it while driving. Good idea!

 

[Ken226]

Also, after a search I came across this old thread.

Similar symptoms. After a rebuild, his engine would die after warming up to temp.

His issue ended up being:

"Bottom Line Up Front (BLUF): I believe that my issue was a faulty/malfunctioning/damaged PCM which might have been caused by a badly corroded engine to heat shield grounding strap. Once PCM and grounding strap was replaced I have had zero stalling issues. Continue reading for full write up."

Here's the thread.

2012 5.7L Hemi Stall

First I want to say thanks to everyone’s contribution to similar issues in this forum and many others as it has helped me through the troubleshooting process (just over 3 months). Below is the conditions, symptoms, and steps/actions taken to correct the dreaded random stalling issue. I did all...

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