Hey guys I have a small problem here, everytime i start my car the rpm's stay around 1500-1700 and slowly go down from there after about 20 seconds until its at normal idle. Any idea of what causes this and what I can do to fix it? BTW the only mods on the car right now are intense stage 3 and injen intake, everything else was stripped off.

bump!

 

Normal in cooler weather.
Cooler engine temp causes motor to start difffernt so it doesnt stall.(Like a automatic choke coming on).

 

Yea but it has been doing it in the summer months too, i just havent thought of it being a problem until now because it is talking a little longer to idle now than before

 

mine does that it starts at like 1400 rpms and eventually drops to about 900rpms when the motor is warn

 

Well is that bad or anything to worry about? What do you mean the motor is warn?

 

i meant warm sorry

yea once the car is up to temp it idles normally i dont see it as a problem

 

oic cool, so its not a bad thing? do you think if i changed the spark plugs or anything it will make a difference?

 

Motors go through a warm-up cycle before a load should be placed on them. The reason that they do this is because when a motor is not running there is nothing pushing the oil through the motor so it all collects in the oil pan. When you initially start the motor you don't want the additional stress of a load on the motor until you have already spread oil and heated up the motor to the more optimal operating temperature.

That is why your motor runs at a higher RPM for a few minutes once you start and eventually drops down again.

Being that you have the intense stage three I imagine you also have an enhanced cooling solution and I think I saw a CAI. All of these things help the car breathe easier. Not make heat and dissipate heat faster under load. That also means the motor takes longer to initially warm up.

 

Having the stage 3 requires the air con to be unhooked does it not.
If so make sure you dont have it on defrost or the rpm may be higher to compensate for the air con load.

 

that's gm stage 3.

 

your car is supposed to do that. It doesn't have anything to do with the outside temp, just the coolant temp.

as your coolant temp rises your idle should go down. Although it does seem like 1500-1700 is pretty high. Usually mine goes to 1200 TOPS. But then again my car hasn't seen temps under 45 degrees. Could be your aftermarket tune has the idle raised at lower temps as well.

 

How much vacuum are you seeing at a warm idle ?

 

as long as it settles back down theres no problem.
its completely normal for an engine to have a higher idle when you first start it with cold coolant.