idle issues while driving (after biss adj)

[chisox7858]

so when i start my car, it idles ok, sometimes it will idle around 300-400 then go up around9. when im driving and coming to a stop, i hit the clutch, the rpms fall, but fall to around 300 then go back up to 9. why does it do this? i cannot seem to get my car to idle right and ive tried adj that biss screw but it doesnt seem to help that much, it changes it but the rpms still fall. say if i was idling at 1200, the rpms would fall around500-600 then bounce back up.

 

[doggo]

Check your ISC.

 

[Spooling99]

Did you adjust the biss while your car was at normal operating temp if you did it when the engine was cold your idle will be off. Your car will idle higher when its cold then when its warm.

 

[chisox7858]

yea, i made sure the car was fully warmed up.

 

[Spooling99]

well adjust it again till it holds 900 fine. If it goes bad again check the ISC or the FIAV

 

[freshlane]

did you ground the proper pins when adjusting the biss?

 

[chisox7858]

idk. i just turned the car on, drove it around, let it sit for a few min, turned it back on the turned the screw till it went to about 900. i am a little new to this

 

[chisox7858]

i also had a check engine light a month ago, it was my isc. i took it out, cleaned it and the cel went away. could the thing be bad?

 

[7"exhaust_tip]

just to put this out there...when my car had a super leaky bov (egay type s) it would do the same thing. so if you haven't already, check for boost leaks.

 

[freshlane]

My fault. I guess it is difference for 2gs

 

[JohnnyC]

1G's have an O-ring on the Biss screw. That might need replacing.