rough idle and exhaust smell

1998 PONTIAC SUNFIRE
70,000 MILES • 4 CYL • FWD • AUTOMATIC
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JCAIN
  • MEMBER
  • 3 POSTS
I have a 1998 sunfire Gt with 70,000 miles. When I first start up the car two things happen. 1) my idle wants to "serge" between about 700 & 1200 RPM's. 2) at the same time my exhaust sputters and smells like un burnt gas. When I back out of my driveway, sometimes my idle surges and I either have to kick the gas pedal, or put it in neutral. as I drive this stops. It only happens durring the initial start up. What could be the cause of this, and how can I fix it ?
Nov 13, 2010 at 6:15 PM
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RASMATAZ
  • ✓ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Try cleaning out the idle air control valve and test the throttle position sensor-
Nov 13, 2010 at 6:21 PM
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JCAIN
  • MEMBER
  • 3 POSTS
thanks for the advise, I'll try to find the idle control valve. As far as the TPS this has been replaced twice in the last 2 years. do these things usually go out like this, or is it maybe some other issue?
Nov 14, 2010 at 3:08 AM
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