Rev Issue

[Danino]

I was wondering if anyone has ever had an issue with their revs not dropping after letting off the throttle. It isn't constant but it is very frequent. Whether it's between shifts, in neutral, or even in gear and off the gas, the revs stay at whatever speed it is at and occasionally rise in revs. I remember reading some where it is potentially something to do with a vacum but I can't recall where I read it, nor did i find anything that looked relavent in a search. Any thoughts?

 

[cposk]

Search idle hang. I have seen threads that claim the solution is anywhere from running a bottle of injector cleaner to a loose ground to the PCM.

Mine got better after changing plug wires, but I still get sometimes while when the motor is hot/idling for a while.

 

[EllowViper]

Idle Air Control (IAC) valve. It has a stepper motor that varies the amount of air entering the intake to manage idle characteristics. It might be sticking/gummed-up based on engine, atmospheric, or other operating variables. Easy to clean with some spray solvent, WD40, or other petrolium distilate.

 

[Steve-Indy]

Hard to guess Viper year. If a 1997, COULD also be well known intake manifold gasket issue.

 

[Danino]

I always forget to put the year. I it's a 98 GTS. I'll look into all of those possibilities, thanks.

 

[Steve-Indy]

Since it's a 1998, the intake manifold gasket issue is probably out of the running (unless you happen to see a problem)...from an old post:

"You said the intake manifold was a 1997 GTS issue. This is a 1997 GTS, so I guess I should have that done. Mine was mad in 09/97 and from what I found on the forums, anything prior to 11/19/97 needs to be replaced as there was a defect in the manufacturing of the gaskets."

Good luck !!