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Hesitation Issue

rs102486

By rs102486
in Ask A GM Technician

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rs102486 Enthusiast

rs102486

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I have a 1995 Chevrolet G20 (83k miles) that has a hesitation issue. After taking off from a stop, it will hesitate with no pedal response then run as normal.

 

Everything is new, plugs, wires, cap, rotor, fuel filter, EGR, Fuel pressure regulator, o2 sensor and coolant temp sensor. A new TP sensor made it worse, and made service engine light come on. Put original TP sensor on and service engine light went off. There are stored codes, and fuel pressure is 12 PSI (drops to 10 PSI after sitting fr 10 minutes).

 

Intake gaskets were just replaced due to leaking coolant.

 

Any ideas?

 

thank you.

rs102486 Enthusiast

rs102486

Posted
  • Author
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I have a 1995 Chevrolet G20 (83k miles) that has a hesitation issue. After taking off from a stop, it will hesitate with no pedal response then run as normal.

 

Everything is new, plugs, wires, cap, rotor, fuel filter, EGR, Fuel pressure regulator, o2 sensor and coolant temp sensor. A new TP sensor made it worse, and made service engine light come on. Put original TP sensor on and service engine light went off. There are stored codes, and fuel pressure is 12 PSI (drops to 10 PSI after sitting fr 10 minutes).

 

Intake gaskets were just replaced due to leaking coolant.

 

Any ideas?

 

thank you.

 

supposed to say "no stored codes" sorry.....

8.1HD/ALLISON Senior Enthusiast

8.1HD/ALLISON

Posted
Posted

If intake gaskets were replaced, distributor had to come out. I would start by checking the timing. Should have an EST bypass wire (electronic spark timing) to disconnect when setting the base time. Not sure where it would be on a G20. The trucks are usually on the firewall behind the black power distribution panel. Single wire, I think they are brown and black? G20 might be different though.

rs102486 Enthusiast

rs102486

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Posted

thanx....fuel pump was checked sposed to be 9-13 PSI, my pressure was 12.....dropped to 10 after sitting for 15 minutes.....mechanic said fuel pressure is within normal limits....also has a new fuel filter

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