Q -Jet carb help please?
Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,327
Likes: 5
From: 2010 C6 Grand Sport Convertible
Q -Jet carb help please?
My '78 has a replacement Edelbrock Q-Jet. The other day, I backed out of the garage, put her in drive and stepped on the gas, only to experience a backfire and hesitation on acceleration. The engine struggles as if the choke were partially closed, which it's not. No more backfiring has occured, only a bog on acceleration until I push the pedal down harder and get past that point. Nothing looks bent down the throttle openings. Carb cleaner down the carb while it's running hasn't helped either. I phoned Edlebrock yesterday. Edelbrock no longer sells nor supports the Q-Jet line of carbs, and would love to know where to begin to trouble shoot.
Thanks in advance.....
Mike
Thanks in advance.....
Mike
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
Make sure the accelerator pump is giving you a good shot of fuel into the primaries when you step on it. With the motor & air cleaner off rotate the linkage to WOT and observe. Other than that, go over the ignition timing, check advance. But like you said bro, it's just a place to start.
Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,327
Likes: 5
From: 2010 C6 Grand Sport Convertible
I was reading Lar's tech notes last night. It has NO bog at all when I'm revving the motor in park. Once I drop it in drive and torque brake the car, the motor hesitates, bogs then finally pulls. So this condition is noticable when under load. I had replaced the fuel pump 6 months earlier. I'm wondering, since its a condition under load, if the $42 Advance Auto fuel pump hasn't taken a crap? Is there a somewhat reliable way to test the pump without a pressure gauge?
Mike
Mike
Last edited by 78pacer; Jun 12, 2008 at 06:47 AM.
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