Sure upon startup

[cableface]

Lately when I start my engine, it surges up to about 1500-2000 rpm then immediately comes back down. Anyone have a clue what could be causing it?

[BillionPa]

mine does that too, thought it was normal

[cableface]

mine does that too, thought it was normal
It's not normal for me. I mean, the rpm's would always go a little above idle speed before settling down but never to 2K. It just started this within the last couple days. Sometimes it will surge twice before finally coming to idle speed. Like I was pumping the gas or something. The behavior is certainly not normal...

[BillionPa]

well, the ICV controls air flow to the engine at startup, by opening then closing as soon as the ECU tells it to.

so its either the ICV not closing fast enough, or the ECU not sending the signal at the right time.

the ECU probably isnt the problem.

[cableface]

Well, today the car has started surging when I coast, but only when I coast. When I am at idle, it does the normal slightly rough idle. Could it be the MAF sensor, or do you think it's still the ICV? Is there anything else? Is there anyway to test other than just replacing the parts?

[632 Regal]

clean the ICV, mine was real sticky and was causing the infamous O2 code

[cableface]

clean the ICV, mine was real sticky and was causing the infamous O2 code
What should I clean it with? Brake Parts cleaner okay?

[BillionPa]

i used carb cleaner ( a whole can ) and it did the trick. i would suppose brake cleaner is ok. carb cleaner contains one extra chemical to remove throttle body deposits, which there are a lof it in the ICV.

[CharlesAFerg]

I cleaned the ICV, but every once and a while (The cracked air intake manifold gasket that I replaced helped a bunch) but still every once and a while, If, for example, im in D, going down a hill and I get up around 50 or greater, I get the check engine light and the gas does NOTHING. Sometimes it turns on and off for a sec, but it turns off once i slow down and i get power. This is related to the old problem I had (which like I said diminished greatly with the new part) where i would be on the freeway and it would be the same problem, but a much greater extent and gas would do nothing and it would occur after / during going down a hill...
I also have a fairly rouch idle.. My ICV is spotless, and all the hoses are intact...
It's wierdddd

[cableface]

I cleaned the ICV, but every once and a while (The cracked air intake manifold gasket that I replaced helped a bunch) but still every once and a while, If, for example, im in D, going down a hill and I get up around 50 or greater, I get the check engine light and the gas does NOTHING. Sometimes it turns on and off for a sec, but it turns off once i slow down and i get power. This is related to the old problem I had (which like I said diminished greatly with the new part) where i would be on the freeway and it would be the same problem, but a much greater extent and gas would do nothing and it would occur after / during going down a hill...
I also have a fairly rouch idle.. My ICV is spotless, and all the hoses are intact...
It's wierdddd
I really dont have my problem narrowed down at all. I'm starting with cleaning the ICV, then I may replace it. I dont know. It could also be a vacuum leak, cracked gasket, or the MAF. I'm at a loss. It's running kind of crappy right now. It's driveable but the power is low. :(

[BillionPa]

i have yet to get a check engine light after replacing the charcoal canister, i got em all the time at high speeds/low prms with my foot completely off the gas before that.

PCV systems and the brake booster are also potential vacuum leaks, the former much more likely.

also the throttle body and intake manifold gaskets could be shot considering the ages of your cars.