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Matt J
Matt J, Chevy Technician
Category: Chevy
Satisfied Customers: 1399
Experience:  10+ years automotive tech, 5 years of experience in a GM dealer
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1999 Chevrolet Silverado 2500: hesitation in acceleration after a stop

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I have a 1999 Chevrolet Silverado 2500. It has a hesitation in acceleration after a stop. It doesn't happen every time I stop and go, but it happens frequently. It seems to run rough and have a longer hesitation when the engine has been sitting and cold. I replaced the spark plugs, spark wires, fuel filter, air filter, and 1 oxygen sensor that wasn't working properly. Also there was a leak in the intake manifold gasket which has also been replaced. The truck does run smoother but the problem still exists. I am not sure what to check next. Please help.



Hello my name is XXXXX XXXXX I will be more than happy to assist you.


Has the check engine light come on or have you had it scanned to see if there is any codes stored in the PCM?

Customer: replied 7 years ago.
The check engine light was on and it was scanned. But I am not sure what the scan results were other than the O2 sensor needed to be replaced. I had a mechanic do the work and now the check engine light doesn't come on anymore.
Does it run ruff at all just at idle?
Customer: replied 7 years ago.
It doesn't run rough at idle except on the most extreme cold days and only until it warms up. It seems to "boag down" or hesitate on acceleration after the first start up in the morning. But idle seems to be okay. The truck has 130,000+ miles on it.

Lets try this first. Remove the intake tube from the throttle body, and clean the carbon out of the throttle body. See if this helps, if not let me know and we will go from there.

Customer: replied 7 years ago.
how do I find your profile again? do I need to sign up for something long term with this site?
No all you have to is login, click on My Questions at the top of the screen, and click on this question. Then just post back to me.
Customer: replied 7 years ago.
I am not a mechanic. since I cannot recognize what is and isn't the specific tube on the throttle body, I will not be able to do the work. is there some other probable explanations I can refer to the mechanic who will work on it? I just don't want to be takin for a ride at the dealership with a not so good rep? I don't have many options here for where I go. I appreciate your help.
thank you!

This is something you could do yourself. Here is the instructions.


Air Cleaner Resonator Outlet Duct Replacement

Removal Procedure

    Object Number: 832066  Size: SH

  1. Loosen the clamp and separate the air cleaner outlet duct at the mass air flow/intake air temperature (MAF/IAT) sensor.
  2. Loosen the clamp and separate the air cleaner outlet duct from the throttle body.
  3. Remove the radiator inlet hose clamp from the outlet duct.
  4. Remove the air cleaner outlet duct.
  • Inspect the throttle body bore and the throttle plate for deposits. You will need to open the throttle plate in order to inspect all surfaces.
  • Clean the throttle body bore and the throttle plate using a clean shop towel with Carburetor cleaner
  • Install the air cleaner intake duct.
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