I have a '97 Ram 3500 and when I turn the key to the off position the truck will keep running from anywhere from a few seconds up to a minute or so. And sometimes it will shut right off. I am thinking that it could be an ignition relay. Any thoughts on what might be causing this would be appreciated. Thanks for your time.

 

Bumping up and moving the 2nd Gen

 

It is called Dieseling. When the engine continues to run.
Haynes manual says
1 Idle to high
2 Fault in fuel / electrical system
3 engine running too Hot Check you radiator / waterpump / thermostat

Jeff

 

i also have the same trouble with a '98 5.9ltr. I have a manual and have changed my thermostat and dont think its overheating (as long as the factory temp gauge is reading correct) replaced the iac valve, unless i'm mistaken the idle on a '98 is computer controlled so i think thats ok. I have also started running 93 oct.. If anyone has had thisproblem and fixed it I would love to know what their soloution was.

 

Replace your ignition switch.

 

forgive my ignorance,butdo you mean the keyed switch on the colume. Or is there a relay that you are refering to.

 

I am not sure if there is an ignition relay or not... but, if your truck still runs for a bit after you turn the key off, that really should not happen. When you turn the ignition off, there is no power to the fuel pump, coil, or injectors..... in order for the truck to be dieseling, it would need fuel..... if the PCM isn't firing the injectors, where is the fuel coming from?

So, what I suspect is happening, is your ignition switch is sticking...... and leaving things powered for a little bit, after you turn the key off.

How does it run for the time the key is off? Is it smooth? Rough? Does the exhaust smell like ........ feces?

 

it doesnt do it every time ,but it sounds what you would think of a typical old car sounds like when you cut it off. Its not extremely rough but it is a little rough a couple chugs and then it dies. The exhaust seems to be normal,but i have noticed when i open the door on the passenger side to let my kids out i can smell gas. It didnt used to be that way but i though maybe it was because of the (don't know the actual name of it) round gas vapor can was right there.The truck is lifted so its kinda right there. thanks for all your feedback so far.

 

Start with doing a leakdown test on your injectors.

 

thanks for the advise but im not familier with doing a leak down test on injectors.