Closed/Open loop idle
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Car: 1985 Camaro Iroc-Z
Engine: LB9
Transmission: 700R4
Axle/Gears: 3.42
Closed/Open loop idle
When you first start it up cold, runs rough for about 5 minutes, idling extremely low but not stalling
After it warms up it starts runnin good but with a high idle, around 2000-3000rpm's
Vacuum gauge shows around 20 pounds, 305 LG4 CC-Qjet
Any ideas? thanks
After it warms up it starts runnin good but with a high idle, around 2000-3000rpm's
Vacuum gauge shows around 20 pounds, 305 LG4 CC-Qjet
Any ideas? thanks
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Welcome aboard thirdgen.org.
After it warms up, do the RPMs drop when you tap the throttle?
Sounds in general like you've got choke issues. The choke pull-off probably isn't giving the butterfly a little nudge open as soon as the engine starts. The high idle cam may also be sticking.
By the way, that has nothing to do with closed or open loop. The choke and idle speed are completely independent of the computer.
After it warms up, do the RPMs drop when you tap the throttle?
Sounds in general like you've got choke issues. The choke pull-off probably isn't giving the butterfly a little nudge open as soon as the engine starts. The high idle cam may also be sticking.
By the way, that has nothing to do with closed or open loop. The choke and idle speed are completely independent of the computer.
Last edited by five7kid; 10-14-2008 at 02:30 PM.
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Car: 1985 Camaro Iroc-Z
Engine: LB9
Transmission: 700R4
Axle/Gears: 3.42
Re: Closed/Open loop idle
When u give it a little, sometimes it'll drop 200-500 RPM or so, it never goes to where it should.
Sometimes when it does this, it'll keep gaining RPM and u have to tap it so it doesn't red line
this may be related, i know nothing of carbs but my uncle "supposably" did, He was playin with my carb and i noticed a spring was just sitting there when he got done..... wasnt the big spring on the driver side, its still in there
it was probably 2-3 inches long? pretty skinny, has 2 loops on each end. I've looked through the carb exploded diagrams and cant find what it is. Kinda hard to replace something when you dont even know what it is.
Thanks for explaining its independant, didnt know that
Thanks for the welcome
I kinda wanna take it somewhere and have them tune up the carb and make sure everythings proper, but i dont wanna take it somewhere and them charge me money and not do anything and rip me off.
Sometimes when it does this, it'll keep gaining RPM and u have to tap it so it doesn't red line
this may be related, i know nothing of carbs but my uncle "supposably" did, He was playin with my carb and i noticed a spring was just sitting there when he got done..... wasnt the big spring on the driver side, its still in there
it was probably 2-3 inches long? pretty skinny, has 2 loops on each end. I've looked through the carb exploded diagrams and cant find what it is. Kinda hard to replace something when you dont even know what it is.
Thanks for explaining its independant, didnt know that
Thanks for the welcome
I kinda wanna take it somewhere and have them tune up the carb and make sure everythings proper, but i dont wanna take it somewhere and them charge me money and not do anything and rip me off.
#4
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Is the spring about the same length as the one still on? The stock configuration had a smaller diameter spring inside the larger one. If you only have one, it might not be pulling back hard enough on the throttle arm.
Make sure the choke thermostat wire on the passenger side of the carb is hooked up.
Make sure the choke thermostat wire on the passenger side of the carb is hooked up.
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