Ok, like the title states my car has a high idle, but only when I start the car on a cold morning. Just this morning when I started up the engine it idled at 2000 rpm then went down as the engine warmed up. It started doing this first when it start sleeting awhile back and has started to do it again. Any ideas on what the problem could be?

 

What kind of Hyundai is it?
the 01-02 Elantra have a TPS problem and should be replaced if it has a "Dae Sung" brand TPS, then the Batt disconnected for at least 20 mins to clear the ECM of anything it has learned with the old TPS, there is also a TSB on re-flasing/upgrading/reprograming on these ECMs

If it the older Elantras 96-99, or 97-01 Tiburons, also check if it has the "Dae Sung" TPS if it Does it should be replaced, they have a tendancy to give a higher false reading to the ECm which thinks the throttle is open and gives more fuel and giving you a higher than normal idle.

hope this helps

 

Also when cold, the idle should normally be higher. Granted FT Worth texas is hardly "cold"...

how "high" is "high"? (please state rpm)

Also...how long does the idle stay "high"? It should drop back down once the engine coolant temp needle reaches the bottom of the normal zone or shortly thereafter.

 

I think I have a TPS problem. When I put it in neutral while in motion, the car idles at 1000 RPM. But once I stop, it goes down to 700 RPM. What should I do? How can I replace my "Dae Sung" brand TPS? Which TPS do I need then? Should I go to the dealer? And two last questions: where did you get that info? Is it an official recall on 2001-2002 Elantras? Thanks in advance.

 

Technical Service Bulletin No. 01-36-011
issued Nov.16/01 model- 2001 elantra XD
vechicles affected All 2001 model year elantra XD with the number "1" in the 10th position in the VIN.

 

the type of TPS should be the "Kefico" brand

 

It's a 2000 Elantra, an what I mean by high is 2000rpm. Like Random said though it does drop down to normal once the temp gauge reaches the normal area. But also I notice that when I tap the gas when its idling high the rpms drop down to 500rpm then shoot back up, almost as if there is a vaccum.

 

If you can...check under the hood next time this happens.

Does the throttle cable/trottle butterfly move, or is the RPM going up independant of the throttle cable?

Your throttle cable can be too tight, which would cause it to idle high when cold, then drop down when warm...but not all the way up to 2000 rpm.

I would check your Idle Air Bypass valve wiring connection, and also check your TPS wire connection. Also...check your brand of TPS as suggested above. It can't hurt.

 

Problem solved, the high idle was due to two problems. One was what random said, cable being to tight, and then also what jaws said about the TPS. I had the right brand, just bad luck that it went bad. Thanks guys the Elantra runs like new.

 

The Tps problem plauges all the Tiburons and Elantras from 95 to now.