Hesitation problem. Need some help here guys
#1
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Car: 1984 Chevy Camaro
Engine: 305
Transmission: 700r4
Axle/Gears: 7.5in 10 bolt with 3.08
Hesitation problem. Need some help here guys
I rebuild my 84 camaro's 305 engine along with the carb. It runs great the only problem is if I'm at a red light or stop sign or if I have to pick up speed, I can't easy the pedal otherwise it hesitates. I have to give it some serious gas. I know if it was a accelerator pump problem it would hesitate with heavy acceleration. Any ideals?
#2
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Re: Hesitation problem. Need some help here guys
You rebuilt the carb.....do you have the tools and gages to set mixture control solenoid limits?
How's the float level and float drop?
Did you uncap the idle mixture screws and remove them? Is the idle mixture adjusted correctly?
I'd still check the accelerator pump circuit. Look down the carb throat (engine off) and slowly open the throttle to full. Even with opening the throttle slowly, the pump should still squirt just as it starts to move.
How's the float level and float drop?
Did you uncap the idle mixture screws and remove them? Is the idle mixture adjusted correctly?
I'd still check the accelerator pump circuit. Look down the carb throat (engine off) and slowly open the throttle to full. Even with opening the throttle slowly, the pump should still squirt just as it starts to move.
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Car: 1984 Chevy Camaro
Engine: 305
Transmission: 700r4
Axle/Gears: 7.5in 10 bolt with 3.08
Re: Hesitation problem. Need some help here guys
Th idle mixture screw caps r off. And i used a vacuum gauge to get highest vacuum. Accelerator does squirt a small amount of gas when throttle is slowly pushed. And no I dnt have a air/fuel mixture gauge
#4
Supreme Member
Re: Hesitation problem. Need some help here guys
Unless you re-establish a baseline by having the carb adjustments correct, it'll be a crap shoot finding and fixing the cause of your off-idle hesitation.
Hopefully, the link might help. I wonder if you can rent the gages and adjusting tools from Autozone, etc.
http://quadrajetparts.com/rochester-...h-t-12_19.html
Edit: Here's another link with tool numbers.
http://www.chevyasylum.com/tech/carbtool.html
Hopefully, the link might help. I wonder if you can rent the gages and adjusting tools from Autozone, etc.
http://quadrajetparts.com/rochester-...h-t-12_19.html
Edit: Here's another link with tool numbers.
http://www.chevyasylum.com/tech/carbtool.html
Last edited by paulo57509; 08-25-2012 at 06:08 PM.
#5
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Re: Hesitation problem. Need some help here guys
Check the fuel pump pressure, too!
#6
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Car: 1987 SC/1985 TA
Engine: 350/vortec/fitech
Transmission: T56
Axle/Gears: 3.27 9-bolt
Re: Hesitation problem. Need some help here guys
If this is the computer controlled q-jet, AFTER setting the mixture control solenoid limits, you'll likely have to set the idle mixture screws and IAB for dwell at idle. If dwell is out of whack so that the ECM can't command a proper air/fuel ratio you'll get off-idle hesitation.
Did you return the settings for the idle mixture screws, rich stop, lean stop and IAB back to their original settings on rebuild? Did you verify TPS function and setting at idle? Have you confirmed base timing and proper timing advance?
You won't be able to get the gauging tools from Autozone, but come back, answer some questions and I can help you get there.
Did you return the settings for the idle mixture screws, rich stop, lean stop and IAB back to their original settings on rebuild? Did you verify TPS function and setting at idle? Have you confirmed base timing and proper timing advance?
You won't be able to get the gauging tools from Autozone, but come back, answer some questions and I can help you get there.
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Car: 1985 Trans Am
Engine: LG4
Transmission: 700R4
Axle/Gears: 3.08
Re: Hesitation problem. Need some help here guys
I have the very same issue that the OP is experiencing. I bought my '85 T/A last October and the car is equipped with the 305 which is completely stock. The car idles fine at 700rpm after warmup. I believe the carb is also original. I have often wondered if the accelerator pump is shot. I went to a site called www.florida4x4.com/tech/quadrajet/index.php that had a lot of good information. I just haven't been annoyed enough to take it apart. Oh, and the timing is spot on and there are no other engine related problems, only the off-idle hesitation.
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#8
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Car: 1987 SC/1985 TA
Engine: 350/vortec/fitech
Transmission: T56
Axle/Gears: 3.27 9-bolt
Re: Hesitation problem. Need some help here guys
You can verify proper booster pump action by looking for a fuel shot into the primary barrels as the throttle is opened. You should see two streams of fuel going into each bore.
Probably not the issue if the hesitation only occurs on light throttle opening.
Probably not the issue if the hesitation only occurs on light throttle opening.
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