My car has had a problem recently. Whenever I am coming to a stop, once i get down to about 15 miles per hour my rpms start going crazy. they will drop to about 400 then jump to about 2800, when i come to a complete stop it continues for about 1-2 seconds then it will either turn off or stable itself at 850 rpm's. I am changing the spark plugs today to see if that helps.

Has anyone had this problem? if so how was it resolved?

 

sounds like a problem with your tune... I doubt plugs will solve an idle issue like that.

 

X2

The tune would be the reason.....unless a sensor fell out..........so it's the tune.

 

If the tune didn't change and it ran good before with the same tune, check your intake manifold gasket, supercharger gasket, and throttle body gasket, and also all hoses, fittings and lines to and from the manifold and supercharger. Sounds like you may have a vacuum leak and the PCM is overcorrecting it with spark.

 

have the mas air cleaned.

 

X3..

 

Thanks, Im in process of trying to get Hp tuners for myself, but in the mean time i will check all hoses and gaskets.

 

Bump for suggestions.

I replaced the O2 sensor and the mass airflow. replaced my CAI with the stock air bow and still have the Idle problem.

 

turn off the a/c
???????

 

The problem starts as soon as i turn on, A/c has not been turned on.

 

vacuum leak.

 

wow good to see someone with the same problem as me, but i didnt mean that in a bad way. It only happens to me when i have my a/c on , and it was going on before i got my stage 2 in so it cant be the tune. Im taking it in on thursday and see what dealer says

 

yea that happens to me also but not as bad as ur talking about,b/c my car never has cut off before on me and my rpm's don't quite jump that high maybe about 1500RPM's and also i noticed that my Injen intake makes it do that trust me on that at least. Had to take the car back to the dealershiip for warranty so the intake had to come off and when i got the car back i noticed it wasn't doing the rough idle deal but right after i put the intake back on the **** started doing it again my 2cents

 

Damn thats weird, you found the problem though thats good, i hope its not my intake.

 

its not the intake it is gm sombody just made a thread with the tsb and recall for our cars and the idle issue is one of them many cars on here do it its normal

http://fr33k.5gbfree.com/06-06-04-039.htm

 

Thanks for the info, Ill be taking my car in soon say what they tell me hopefully it works.

 

I will have to check everthing on mine.....I have had a few tunes and help from people to try to fix my idle issue when coming to a stop in gear....My car is fine out of gear (well it doesnt stall) but it still bounces.

 

This is an OLD TSB, look at the date! It is really easy to prevent the fluctuation by driving changes....when slowing down below ~20 mph, throw it in neutral (I think the manual suggests this as well). Our electronic throttle tries to prevent stalling by throwing fuel and timing into the engine when it reaches a low RPM threshold. I've noticed that the recovery from this stall-prevent routine in the ECM can take a few rounds of automatic on-and-off throttle applications before the idle stabilizes.

Thank you, drive through...

Another interesting fact about our electronic throttles...

You may have noticed that when you take off (its really easy to do downhill) in first with NO THROTTLE, that the RPMs climb. This is the stall-prevention giving you more gas in first gear-idle than in neutral-idle and you can use it to your benefit in traffic.

 

Trust me I tried everything except reflashing, It still gives me problems coming to a stop. I was wondering if it could have anything to do with the clutch?

 

did you check for fouled plugs? what is your boost gauge reading at idle? you might want to consider getting reflashed at the dealer since whenever there have been issues with idleing, it seems like ECM-recalibration was the fix.

 

Thats my next step. Everything else has failed.