I've looked at a couple of the other "B16 High Idle" posts and none of them seem to be what Im working with. I went to help a friend figure out why his car was surging at idle. Unplugged the IACV and it got a rapid surge, plugged it back in and had a slower surge again, so we finally figured it was the TPS. replaced it and no more surge but its idleing about 2900 now, it fell to about 500 rpms stayed for about 1 minute and then shot back up and stayed there. it was running great until he put a Skunk2 intake manifold and 70mm throttle body in it (it also has sit for about 2 yrs). Any ideas? Thanks for ur time and help, Wil

 

Isnt there a screw you have to adjust?

 

very high idle usually caused by a vacuum leak

 

vacuum leak is very possible, make sure all ur hoses are connected and or are sucking/blowing.

 

also check and adjust throttle linkage on throttle body if necessary..

 

Check for vacuum leaks on the new intake, maybe a bad casting? Adjust the air idle bypass screw. The throttle butterfly should be closed at idle, and the idle circuit all bypasses thru the bleed. 2900 rpm is probably a vacuum leak, check by spraying starting fluid around the intake, and listen for the idle to get faster.

 

Thanks for all the help. Vacuum leak is what i was thinking also. Ill go through and check it all out and get back with more info. Thanks, Again.

 

If the 70mm TB has an FITV I would put money on that being the issue.

 

FITV?

 

Fast Idle Thermal Valve

It's under the throttle body and is an extremely common cause of this.

Take the two cover plate screws off and turn the ceramic piece almost all the way in... Replace cover. Simple as that.

 

sorry i been away so long but thanks for the help and ill try the FITV as we cant find a vacuum leak any where.