High idle

[cartert]

1988 7m-gte

Mods: CT26 57 trim with billet compressor wheel, 3” divorced downpipe, 3” exhaust with Apexi N1 muffler, Walbro 255 with 12V mod, cone air filter, 2.5” intercooler piping kit.

I have all of the parts to complete a lexus/550 mod, but wanted to address my high idle first.

Idles consistently around 850-900rpm. Checked the timing about a year ago and it was at 10 degrees with the Te1 and E1 connected. Idle was still around 900rpm after removing the jumper.

Several years ago in an attempt to avoid boost cut, I drilled out the plug on the stock AFM that exposes the air screw. I backed the screw all the way out, further research shows I should not have done that. What is the factory position for this screw?

I also messed with the screw on the throttle body. I now have it screwed it all the way in (clockwise). Turning it counter clockwise any speeds up the idle. What is the factory position for this screw?

At some point in time I remember this car idling around 650 rpm. I can not recall exactly when or why it changed, for some reason I think it was associated with me messing with the screws.

Any other items/area’s I should look at to try and correct my high idle?

 

[CrypticRonin]

It sounds like you have more air sneaking by your afm after having messed with the screw there, and you have your idle screw on your throttle plate screwed in to limit that additional air. I would try to mitigate this by screwing that afm in some more and idle screw out. Since you messed with it yourself, you must tune it back yourself. If you're by chance in WI, this would be something I could lend a hand with.