Idle doesnt come down till stopped.

[greddy_1700]

Hey guys, I am looking at buying a second DSM and I just recently test drove a 2g GST yesterday, but it had a weird idle problem that I've never heard of... The car drives great, idles great, but after moving and driving around when you take the car out of gear before coming to a stop the idle stays at like 2000rpm. Now it does this untill the car comes to a complete stop, then all of a sudden it drops back down to a steady 800RPM. Now this is a new problem to me... I cant seem to find any info on this situation.

Any ideas welcome!

The car has some basic mods done to it, like new bov, evo fuel pump, 550 injectors, safc, tre tranny, act 2100 clutch and flywheel, 14b.

 

[pneumo]

DSM's normally have a higher idle when the car is moving, but usually it's only a hundred rpm high.
Rolling idle speed will be even higher when the motor is cold, or if the A/C is on, or if the defroster is on if it's a 2G.
Since the idle dropped down when the car stopped, I wouldn't worry about it.

 

[greddy_1700]

Ok, so the engine was kind of cold, but by the end of the drive it was warmed up nicely. And granted I had the defroster on, but I didn't think that would make the engine idle at 2000RPM...

 

[drewvr4]

Ok, so the engine was kind of cold, but by the end of the drive it was warmed up nicely. And granted I had the defroster on, but I didn't think that would make the engine idle at 2000RPM...

It shouldn't, max idle at cold should be somewhere around 1500 rpm. Any CEL's or other problems with the car?

 

[Boost92awd]

Check the throttle cable, to see if its sticking at all. Sounds simular to a problem I had.

 

[greddy_1700]

It shouldn't, max idle at cold should be somewhere around 1500 rpm. Any CEL's or other problems with the car?

Thats what I was thinking. The car has one cel code but I am told its from him venting the BOV to the atmosphere.

Think the TPS would do this?

 

[drewvr4]

I would think that unmetered air like that would act more like a boost leak then anything, but its worth plumbing that back up and seeing if it fixes it.

 

[Boost92awd]

If your still venting this could be part of, it not all your problem. Venting on a stock MAS FTL.

 

[greddy_1700]

If your still venting this could be part of, it not all your problem. Venting on a stock MAS FTL.

Agreed, the first thing I am doing if I buy the car is throwing on a recirc pipe.

Well I guess thats the first step, If it helps awesome, if not. Well you will see another thread haha.