Question : 660 Gurus: Soaring Idle Issue

[2ndGenZ24]

Hey whats up guys,

First off, my Z24 is a 3400 swapped car. I have an idle issue where the car is idling high (approx 2000 RPM). Periodically the idle will stutter (I am assuming that this is the IAC hunting for a correct idle). I have cleaned out the IAC's pintle so it is free of any carbon build-up.

This problem is an intermittent one. I have even switched out the IAC with the 2.8L one and it fixed the problem temporarily. The problem came back so I reinstalled the 3400 IAC and it was working fine up until last week. I am stumped with this problem. On a side note, I replaced the TPS today and the problem did not go away.

Thanks in advance for any help.

2ndGenZ24

[SuzukiGhostRider]

Well, I was going to say test the TPS but since you tested it already.... I would focus on finding your vacuum leak as I'm going to assume that to be the issue. Get a can of Carb Cleaner and start spraying it around your TB seals and UIM seals etc , with the car running. If it chokes or stutters when spraying an area, you've got a bad gasket. Also check all your vacuum lines and your MAP sensor and brake booster vacuum lines too. GL.

[3XTurboAgain]

who tuned it? does it have egr delete?

[3400-95-Modified]

If you can scan it, whats your TPS voltage when the throttle blade is closed? I'm wondering if its closed too much or open too much making the IAC work to hard or not even be necessary.