High idle
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Car: 1988 gta
Engine: 383
Transmission: 700r4
Axle/Gears: 9 bolt 3:23
High idle
Cruising along at 15 to 20 mph, shift into neutral and it won't go below 1500 rpm. Come to a stop and idle returns to normal. So this car will travel for miles without touching gas pedal. Any ideas? Thanks Mike
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Car: 92 Firebird Convertible
Engine: 383 - First Fuel Injection TPI
Transmission: 700R4
Axle/Gears: 3:23
Re: High idle
Having the same problem - the slow speed "creep" - have to keep riding the brakes. Shift into neutral rpm jumps to 2000 - 2500. Tapping the throttle results in even more rpm.
Got to be a setting in TunerPro to correct this that I'm missing as after a full stop it idles down to the correct rpm setting.
What engine and fuel system do you have?
gw082008
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Car: 1987 IROC Z28
Engine: 305 TPI
Transmission: TKO 600
Axle/Gears: 3.45 (G92 package)
Re: High idle
is yours manual or auto? also, mine (manual) will stay just above 1000 RPMs in neutral while cruising at relatively higher speeds (over 40mph)... I think it's from the air flow being forced in the MAF by the air dam... quite normal I believe... once I slow down or stop it idles down again. But I think you may have to adjust your minimum idle air speed or clean the IAC
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Car: 1987 IROC Z28
Engine: 305 TPI
Transmission: TKO 600
Axle/Gears: 3.45 (G92 package)
Re: High idle
gunked up would cause a choppy idle or even the car to die at idle... what's most important is setting the minimum idle air speed correctly. jump the ALDL and turn key on; wait 30 seconds then unplug the IAC. Remove paper clip (or other metal jumper) from the ALDL and start the car. (Car is now idling without the computer commanding idle air speed). If car does not start keep trying until it does. You may need to use a torx screwdriver to advance the screw that serves as a stopper for the throttle lever. this will let more air in the engine. Once you get it idling, unscrew the stopper screw until car idles at 450-500 RPMs with IAC unplugged. Then you want to turn the car off and plug the IAC back in. At this point, jump the ALDL again and ensure that the TPS is getting correct voltage and that the voltage between idle and WOT is a smooth transition, and that voltage at WOT is over 4.0... then unhook the battery for a few minutes to re-set the computer and hook it back up, start the car, and take off right away and get on it especially in 2nd gear so the computer can "re-learn" fuel/spark timing....
i hope that solves your problem. If you don't understand what I just explained there are plenty of articles that are more clear on here. Made a huge difference for me...
i hope that solves your problem. If you don't understand what I just explained there are plenty of articles that are more clear on here. Made a huge difference for me...
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