The check engine light came on a couple of days ago and I tightened the gas cap and it went away. Yesterday the light popped back on and the engine would idle very rough around 700 rpm in neutral (It is a 5spd). Today it started fine and it was idling normal around 1000rpm and it ran really smooth. After a brief drive it started getting crazy and would idle to 5000rpm in neutral and then drop quickly to 1500-2000rpm and run back up to 5000rpm. I was luckilly right around the corner from my house and brought it home and shut it down. Does anyone have any idea what might be causing this? I own a 2001.5 Elantra GT with about 63k miles on it.

TIA,

Chris

The check engine light came on a couple of days ago and I tightened the gas cap and it went away. Yesterday the light popped back on and the engine would idle very rough around 700 rpm in neutral (It is a 5spd). Today it started fine and it was idling normal around 1000rpm and it ran really smooth. After a brief drive it started getting crazy and would idle to 5000rpm in neutral and then drop quickly to 1500-2000rpm and run back up to 5000rpm. I was luckilly right around the corner from my house and brought it home and shut it down. Does anyone have any idea what might be causing this? I own a 2001.5 Elantra GT with about 63k miles on it.

TIA,

Chris

Check the Idle Speed Conrol (Stepper Motor)

call dealer about a recalled part.My 2000 would go slower and car vibrate the more i stepped on the accelerator in 1st or 2nd gear within 2 blocks. I pulled back in the driveway.The dealer replaced the part -no cost.