rough idle

Hello everyone it has been a while since I have been on here. The last time I had some pblems with my 2002 Hyundai Elantra one of the threads on here helps immensely. I find myself baffled by a loss of power and a backfire. The engine seems to do alright when overdrive kicks in. I also...

___When engine is cold (Florida climate)____ - As soon as the car is turned on I get a really rough idle and/or vibration, then it smooths out - Turning on the AC and/or putting the car in drive make the car idle very rough (about twice as hard as it used to 3 months ago) - If I turn on the AC...

2002 Hyundai Elantra GT 2.0L 140k miles Symptoms: - Intermittent rough idle when hot, slight shutter, surges between 700-800rmp - Intermittent hesitation when accelerating, cylinder 2 misfire when hot and under load - Misfires in all gears under load, mostly when under 2000rpm - Code P0302 when...

Hi all, Recently my 2002 Elantra Auto started throwing a P0302 code, with a rough idle. Read through the various threads here, and my guess is that it's most likely the intake manifold gasket? Seems like that's a common failure for '01/'02 Elantras lately. I replaced the spark plugs (NGK...