idle problem

[zenki]

Something i noticed this week and it drives me crazy. When the engine's warm it idles around 900 rpm. This is good so no problem there. But when i'm driving and i have to come to a complete stop it starts to idle at 1700rpm. So you're standing there at the red light with a high idle. It's so annoying cause it makes you look like idiot. But when i give the gaspedal a little push the rpm drops back to normal.

Could it be a vacuum leak or something? I checked the hoses and they seem to be fine.

[Project D]

I had the same problem 2 or 3 years ago.
It was the dash pot (the little thing under the throttle cable)
When you release the gas pedal slowly, it stay stuck on open postion so your idle stay between 1500/2000. When you give a little tap on the gas pedal it hit the dash pot and so your idle goes back to normal.
For me a little spray of WD40 have resolved the problem.

You can also completely remove it (it's an "eco" thing after all)

[zenki]

^^I checked the dashpot thingy 20mins ago and it goes back really slow. So i had a look on my other ae86 and there it goes back instantly. Seems to be an easy fix.

Thx for the help.

[allencr]

zenki Wrote:...it goes back really slow. ...it goes back instantly.

Try out a 3rd/4th opinion for really slow, instantly is NFG. Should be in between clogged & failed, like landing on a marshmallow.

[zenki]

Here's a picture. I put some wd40 on the little thingy (no.1). And then i undid the vacuum lines and the vtv (no.2) and placed them back. I did help a bit cause i'm not getting it everytime know.

[max_ae86]

There are more things to be checked:
1) check throttle cable for any sign of damage
2) check TB butterfly shaft for free play (replace the seals if necessary)
3) Check TPS sensor according to manual spec.
4) Check butterfly for free play (sometimes it gets loose)