I have a 2000 ram 1500 sport 4x4 with a 5.2 engine. About a year ago, it wouldn't run..Had a new crank sensor installed and it's running like a champ!! About 2 months ago it starts acting up, would start and run fine, but after it's warmed up , if you stop and shut it off, when you start it back up, in about 20-30 seconds it would start running really rough.. Rev it up a few times and it would start running fine. It started acting up more and more- took it to the dealer and they said it had a bad lower intake manifold gasket. Had that repaired! now it starts fine but is back to running rough after 20-30 seconds again... When its running rough it sounds like its sucking air, but my friend sprayed starter fluid/carb cleaner all around the motor and he found no leaks. if your driving when it starts running rough it also sounds like its back firing at the carb/throttle body, if I put it in neutral and give it gas it run's smooth-put it back in drive and it acts up again. If it had a carb and choke I'd swear it's the choke sticking! Any body got any ideas!!!!! Thanks Larry

 

Try cleaning the IAC, disconnect negative battery before doing so. https://dodgeforum.com/forum/dodge-r...n-the-iac.html

Read the plenum sticky. Even though the gasket was fixed , the cat and o2 are surely also no good if the plenum gasket was in fact no good. You need to start there.

 

Thanks I'll trythe IAC.. P.S. The dealer wanted 1800.00 to replace the gaskets, so I had it done elsewhere, and they said that the gaskets were not bad after they removed the intake, *installed new gaskets,cap and rotor=same problem...

 

Pull the upstream O2 sensor out and see if it runs better.