My 2003 Ram 1500 4.7L will intermittently idle rough at a red light or stop sign, and sometimes die out. However, after it dies, just turn the key and it fires right back up! I use to think it only did it when it is cold, but it also does it after warming up. It's currently throwing an EVAP code for a "very small leak". I replaced the gas cap and purge valve, but it still comes on every so often. In addition, the truck sat for 6 months before I got it, but I've been driving it for over 3 months now and I've gone through several full tanks of gas. The truck runs great! However, I do feel considering having a 4.7L V8 that it should have more power. But maybe they lack power normally. This is my first 03 Ram 4.7L.

My questions are...

1.) Could a small EVAP leak cause an engine to idle rough and die, but then start back up again?
2.) Could this be a failing fuel pump as a result of sitting?
3.) Could a bad engine ground cause this issue?
4.) Some of the things I'm reading points to a failing EGR valve. Could this cause this issue?

Let me know your thoughts.

 

1. Rough idle? Could be. Stall out? Probably not.
2. Maybe, but, unlikely.
3. Yes.
4. Not sure on that. My truck doesn't have one.

 

Barring bad spark plugs, TPS and or IAC valve are the most likely culprit.

The small evap leak shouldn't cause any stalling. You need to pull off each end of the evap hoses and squeeze them. Cut off any cracked ends and reattach. Some of these run underneath the truck

 

Have you changed the transmission fluid lately? Or checked it? Mine was 1 1/2 quarts low and it did this in the morning only.