what should a stock gn idol at?

[87grandnat]

i have a 87 gn basically stock/ computer chip exhaust k&n airfilter 160 thermo, and its idoling between 1800 and 2000 rpm it seems high for idol is this ok or not if its idoling to high what do i do to change it, thanks for any help

 

[turborayjay]

The computer chip controlls the idle. 1800 is about 1050 too high. I believe 750 +/- is where most chips idle. Sounds like your tps or iac may need adjustment. Go to gnttype.org and look under the tech section on how to adjust the tps and iac. Both are rather easy with a scan tool or volt meter.

hth

Ray

 

[TurboDave]

Don't rely on the stock tach to read your idle. They are never accurate, and most show that same type of error. At an idle of 800 on my 87, the stock tach shows close to 2000.

 

[boostin6]

If you have a scan tool I would check the rpm with that....I've seen before on my car the stock tach was off by 1,000 rpm...I knew it wasn't idling that high and the scanmaster said 750 rpm and the tach said 1750 rpm.... Just my $.02

 

[87grandnat]

well i can tell that it is definitly too high, it idols likke you are slightly pushing on the gas, i know that the stock tach is probably off, but even by the motor i can tell, i guess its time to break down and buy a scanmaster