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iac counts low

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Old 03-13-2007, 08:27 PM
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Default iac counts low SURGING BAD WARM

Alright Ive cleaned out the iac but I still have problems. It runs good for quite some time and its between 20-40 counts. But after a while it just keeps getting lower and eventually zero. then you can see the tack surge then the motor actually revs to like 2000 2500 and starts surging all over the place. Does this mean the iac is shot? I got good vaccuum so theres no huge leak anywhere.

thanks for the help

95 trans am lt1 stock throttle body

Last edited by bubba24; 03-16-2007 at 02:34 PM.
Old 03-14-2007, 07:21 AM
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You can have a decent vacuum readings but still have a minor leak somewhere. And a minor leak is all it takes to mess with the idle.

Could just be a bad IAC, or there could be a leak. What happens if you immeaditely restart the car when the idle gets messed up? Does the idle correct itself?
Old 03-14-2007, 04:57 PM
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It took off the iac now and i figured I could just see if the pin will move in or out and it does not so it must have went south. I guess order a new one ans see...

thanks
Old 03-16-2007, 12:11 PM
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Car idles around 1000 rpm when started and drops to about 750 as it warms up.
at this point I havent touched throttle. Will idle just fine.
When I raise rpm and let off quickly, it drops to about 500 rpm then surges to about 1200, then drops to about 300 and surges to 1500 then down to about nothing and dies.
When I drive the car, It holds around 1500 rpm until I slow to about 3 mph, then does the surging described about.
Each surge gets a little bit bigger than the last. And it only surges a few times before it dies.

It does this in park. In drive well it just idles faster no surge and i do not need to push on the gas . Once i slow down and idle then bam it surges like crazy. And the tach is shaking like crazy too.

any suggestions

thanks
Old 03-18-2007, 07:20 PM
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okay I found that when I unplug my tps sensor the surging stops but the throttle stays at about 1500 rpm. Now my question is can that sensor go bad even if there is no code and I can read 0.65 volts and the % changes on the datamaster program. it sure looks like it is working on datamaster when I push the pedal. During the surging it does not move but it shouldnt cause I am not moving the throttle.



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