odd IAC behavior
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,241
Likes: 9
From: Houston TX
odd IAC behavior
i'm trying to diagnose a possible ecu or harness problem, and in the process discovered some odd behavior. i was hoping someone could confirm what's considered normal for these cars. (OBD-II LT4.)
if the engine is running and i unplug the IAC, the engine maintains the correct rpm. if i reprogram the idle higher or lower, it still maintains the newly programmed value, so it's not just a case of how far the TB blades are screwed open.
all of the other cars i've worked on would immediately die or change rpm if i unplugged the IAC. only thing i can think of is that the IAC on my vette maintains its last position when powered down, rather than springing closed. otherwise, i have a problem which may or may not be related to the other problem(s) i'm trying to chase down.
thanks for any info.
-michael
if the engine is running and i unplug the IAC, the engine maintains the correct rpm. if i reprogram the idle higher or lower, it still maintains the newly programmed value, so it's not just a case of how far the TB blades are screwed open.
all of the other cars i've worked on would immediately die or change rpm if i unplugged the IAC. only thing i can think of is that the IAC on my vette maintains its last position when powered down, rather than springing closed. otherwise, i have a problem which may or may not be related to the other problem(s) i'm trying to chase down.
thanks for any info.
-michael
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,241
Likes: 9
From: Houston TX
Re: odd IAC behavior (96GS#007)
excellent. thanks so much, i really appreciate it.
i guess the valve isn't spring loaded like most IACs. in any case, that means this isn't related to my problem, i'll look elsewhere.
-michael
i guess the valve isn't spring loaded like most IACs. in any case, that means this isn't related to my problem, i'll look elsewhere.
-michael
