Well I'm in New York for vacation, and I can use my cousins car but dere is one thing wrong with it, it idles past 3000rpm so i was wondering if anyone would know what the problem is, its a fully loaded 2000 Chevrolet Impala.Only in Reverse it goes between 1 and 2 so whenever u switch to Drive it kicks hard, it also does this in Neutral and Park. what the heck is going on but help me plz
Your commentary is appreciated

 

Sounds like a Vacuum leak. It is not shifting right because it is idling so high.

 

It is driveable but its just that when ur driving it would kick off @ 3000RPM

 

if the check engine lite is on, take it in and have it scanned for codes. Good place to start

 

Likely a vacuum leak or 'maybe' an effed up throttle position sensor .

The last late model GM I will ever own, my Z34, had retarded idle issues and it was always another vacuum leak. piece of car.

 

could also be a defective idle air control motor.

 

my suv was doing about 4000 and it was a throttle position sensor
if you know how to repace it , 15 mins to fix it $50 for the part

 

clean the throtle

 

check to see if the detent/downshift cable is caught around the throttle lever.

 

agreed , pay special attention to the iac .