Hello, I have a 2001 monte SS It runs rough at idle. If I hit the gas or hold it at any rpm above 1000 it seems to be fine but when I let go of the throttle and it comes back down to idle it get very rough and stalls. There is no engine light. and i have replaced the Cat., Map & Maf sensors and have done a tune up in the last year. Just wondering if any one has an idea of where to start looking. Thank you!!!:banghead:

Hello, I have a 2001 monte SS It runs rough at idle. If I hit the gas or hold it at any rpm above 1000 it seems to be fine but when I let go of the throttle and it comes back down to idle it get very rough and stalls. There is no engine light. and i have replaced the Cat., Map & Maf sensors and have done a tune up in the last year. Just wondering if any one has an idea of where to start looking. Thank you!!!:banghead:

clean the throttle body/IAC this is usually the area where the engine can't regulate the idle rpm...if dirty stuck, plugged with black goo...

check fuel pressure and replace the pcv ....inspect vacuum hoses and replace as necessary..