Ask a Question
or
Create a Poll
  1. Home /
  2. Questions /
  3. Autos & Motorcycles
  4. / Car Makes & Models
  5. / Makes A - H
  6. / GMC Models

by Ian McCormick on July 1st, 2007

Ian McCormick

Question

Help answer this question below.

Ok I have a 79 GMC with 5.7 L 350. It has a new 4bl carburator and i have adjusted the fuel air mixture. when the engine has been driven for a good 10 to 15 minutes and is warm it will stutter when i floor the gas. Any ideas what it could be?

  • Like
  • Report
Share:
Other

Answers. 1 helpful answer below.

  • by Old School on July 2nd, 2007

    Old School

    First off all, hesitation upon acceleration is frequently an *ignition* problem, not a fuel problem. You should double-check that your distributor cap, rotor, spark plugs, plug wires, etc. are all in good condition. Also make sure that the mechanical and vacuum advance mechanisms on the distributor are working properly.

    One final ignition item is the vacuum source(s) to the distributor vacuum advance. These may be run through a temperature-controlled vacuum switch. If that switch is disconnected or has failed, that could cause the timing to be incorrect once the engine warms up.

    If all that checks out, the next culprit to check is the accelerator pump circuit(s) of the carburetor. The accel. pump is a device that squirts liquid fuel into the carb. throat as you quickly open the throttle. Check that the accel. pump is properly adjusted and that a good dose of fuel is squirted as you work the throttle linkage.

    Apparently, sometimes adjusting the idle circuit to the "best" setting can cause acceleration bog as well (see link below) That's something to look into if all else fails.

    http://www.thecarburetorshop.com/Troubleshooting.htm

    Good luck.

    No comments. Post one | Permalink

Want to attach an image to your answer? Click here.

Did this answer your question? If not, then ask a new question or create a poll.

More Questions. Additional questions in this category.

You're reading Ok I have a 79 GMC with 5.7 L 350. It has a new 4bl carburator and i have adjusted the fuel air mixture. when the engine has been driven for a good 10 to 15 minutes and is warm it will stutter when i floor the gas. Any ideas what it could be?

Follow us on Facebook!

Related Ads

Related Questions

Professionally Researched

ANSWERBAG BUZZ

Gm 5 7 stutter on acceleration
79gmc
350 bogging at idle and acceleration
How much horsepower does 350 5 7 79
5 7 vacuum advance distributor

Answerbag

a Demand Media company