Recently my 02 elantra gt revs @ 3000 rmp when I start the engine in the cold morning. It used to be ~2000 rpm. It will stay at 3000 unless I press the accelerate pedal a bit. The motor eventually revs down to normal ~750 rpm but only after I press the pedal. I replaced the original air-filter with the K&N drop-in a while ago. Can it be the reason? I did not have any problem with the K&N drop-in's on my Civic or Sienna.

 

It's just your engine warming up.

 

why stay @ 3000 rpm forever unless I press the pedal if that is normal warming up?

 

trust me, it's normal. random, can you verify this please?

 

3000 RPM is NOT normal for engine warm up. It staying there untill you press the pedal is NOT normal.

It doesn't do this on warm starts? Only on cold?

I would triple check your Throttle cable wires anyway...one of them could be "stuck" when cold, and only loosen up when warmed up.

 

It does only when cold. This is the first winter my GT is in. Once the mtor is warm, it briefly goes up to 2000 rpm and then down to below 1000.
This morning, it stayed at 3000 rpm for about 35 seconds and then went down to 1000 rpm.
Should I call the dealer ship?
Man! it's 40 min drive from my town.

 

Have your TPS checked out, Hyundai still uses the "Dae Sung" brand TPS, there known for causing drivability problems.

 

Every car I've ever owned has done that when I start it in fridgid weather, even the Mercedes at the dealership do that when it is cold, so whats up?