VERY high idle on stock 92 240sx

[unit77]

This is my sons car so I will describe the problem as best I can....car started smoking black and running erratically......Idle had always went up and down between about 600-1000 and died often but ran ok...long story short,a new Air Flow Meter fixed the smoking and erratic running ...now the damned thing runs great but idles at 2500-3000rpm!!!!!....I have already spent in excess of 1500 bucks on this POS and would like to be able to fix this problem with some help from you guys...TIA

[dkdeleon68]

check the throttle cable for over tightening and lower your idle with the idle adjusting screw

[unit77]

Thanks for your suggestions but,I have already checked the cable and there has been no adjustment to the idle screw

[180fan]

if the idle adjustment screw does nothing for you, you probably have a vac leak. I'd look over that idle adjust screw again.

[unit77]

I will try the idle adjust screw,as soon as I can find it...:>)......the thing that has me confused is,if no one has touched the idle screw,why would it suddenly need adjusted?....the mechanic told me he fixed several vaccuum leaks so I dont think thats it either...it started when I replaced the Air Flow Meter.....thanks

[MOscapinski]

You can try to adjust the TPS and/or the AAC valve. Did you check the ecu for codes?