Hello everyone.

I have a 1998 Dodge Ram Van 1500 with a 5.2L. It has this weird hesitation after 1 to 2 hour cool down. It hesitates and stumbles for 20 seconds or so and then it's fine. I've had it to the mechanic twice so far. Did a complete tune up, a new map sensor and reset the computer. It was generating no codes. Fuel pump is fine with the proper voltage. Now I've changed fuel to Shell V-Power and added Techron.
Anyone else have this problem or any solutions?

Thanks

 

Sounds like a leaking fuel injector. The stumbling could be due to the cylinder with the leaking injector getting flooded. It would take that 20 or so seconds of the engine running to clear the flooding in that one cylinder. You could try running injector cleaner for the next couple of tanks and see if it helps.

 

Thanks for the reply.
It sounds then I'm on the right track. I've been through a 1/4 tank so far and things seem to be changing a little. Just leaving it idling it takes about a minute to act up.

I never thought of a leaking injector. That would make more sense. I was thinking it was carbon on the valves.

I'm surprised it's not generating a code. Is this normal?

Anyway, I plan on a 2 hour drive on the highway with the 4th gear off. It really doesn't get much highway time.

 

The PCM does not generate a "Rich" fault on the MIL (Malfuction Indicator Lamp 'Check Engine'). It will detect and post the MIL for a "Lean" condition.

Your first post stated it acted up after a 1 to 2 hour shut down, now you said that it takes a minute to start to act up. Could you please explain this better?

It should be fine with the OD on for the two hour drive, with a good quality fuel cleaner it should clear up the injectors in that time.

 

It rarely does it when it's cold. The engine will be fully hot and then after sitting for 1 to 2 hours it will stumble after 20 to 30 seconds of driving or about a minute of just idling.

Also after alloro's reply it reminded me of the lack of primed fuel pressure for the last year or so. If the van has been sitting for a while I usually turn the key on for a second or two to let the fuel pump prime things. Otherwise the enigine will just crank for 5 seconds or so before starting.

 

When was the IAC and the IAC ports last cleaned?

 

I don't know what the IAC is? Is it that Idle Air Control? If so where is it? Why would that caue these symptoms?

 

The IAC is the Idle Air Control. Here is a link as to where you can find and how to clean it. Stev did a great job with the explaination and photos. It took me less than 30 minutes to complete including removing and reattaching the "dog house".

https://dodgeforum.com/forum/dodge-ram-van/68174-diy-how-to-clean-the-iac.html

He tells you what and how to do this job. You will need paper towles, q-tips, and carb cleaner spray.

Have fun and enjoy your DIY job.


Kenny

 

Ok. I just cleaned it. It wasn't that dirty.
It doesn't seem to make any difference.

Any other suggestions?

 

A guess:

Check and clean the electrical connection for the fuel pump nearest the tank, and follow the wire (my + was green) back to the PCM. Mine('89) had 5 different connections through different harnesses. I eliminated one.

My other temperature related funkyness turned out to be a failed PCM because a sensor wire(light blue with white stripe) was grounding out on the tranny bell housing.
Man was that a fun and expensive one to figure out. At least I have a couple back up sensors now.