Jbs6891

Hey guys havent been here for a while. Update: Got rid of the 83 Ram and now have a 99 Ram 1500 5.2 L . Well Initially, the truck was very hesitant in running. It idled like crap and had no power. I since have replaced the Cat ( which was definately bad) I also have replaced the IAC sensor, TPS sensor, cleaned the throttle body out with sea foam, new plugs/wires/cap/rotor, and I believe that it is all. Now the truck runs great for the most part. It will start up and idle until the thermostat is about to open then it starts idling rough. Then it will sit and act like it is about to stall then all of a sudden get a second wind and run great. When you are driving it, same thing when it is about to open the thermostat the truck will go from running great to hesitating and acting like it is going to stall and right when you are about to pull over on the side of the road it gets it second wind and full speed ahead again. Now when it starts falling on its face, it backfires multiple times through the throttle body. The check engine light stays off the entire time and has yet to be tripped. I have replaced everything i could possibly think of so please help. Hoping others have run across this before.

RacerHog

.... Hook the scan tool up and head out.... I would look at temp sensors and Long and Short term fuel trim... Cant remember if those had a crank sensor or not.... But mite watch it also....

Mr.4spd

My money's on dirty fuel injectors. Do a few tanks of gas with F.I. cleaner and see if that doesn't help.

pro-tech

They do have a crank sensor Bob, But I would be looking at coolant temp sensor values and O2 sensor. At the point of what you are saying it does the problem is when it is going into closed loop. There are a lot of variables that could cause this and it needs to be put on a good scanner and be performed by someone with the knowledge to diagnose the problem correctly so you don't spend a ton of money replacing a bunch of stuff not needed.. One of the big problems today is electrolysis which will cause a lot of problems and even semi good techs will be stumped... Just my .02 cents... Bill