is this a tbi or a sfi[vortec] engine?
It is the vortec engine, i just wnet and started it and when it is park there is no hesitation or backfire, only when it is being driven.
does the engine light stay on?if so,can you give me the computer codes?
Engine light does not come on, I do not have the capability to get computer codes.
first..if you haven't already,tune it up..new plugs,wires,rotor and cap..the distributer cap and the rotor can give a fit sometimes
you need to check the fuel pressure
these must have no less than 55psi at all times
a clogged fuel filter may restrict the pressure..but,it is very common to have a weak fuel pump in these vortec engine
I have replaced the fuel filter, would it back fire if the fuel pressure was low?
this would be the most likely problem ..sense the engine light does not stay on
a fuel pressure test will confirm this
so,you need to test it first
What is the process for testing fuel pressure?
i will need to switch from chat
give me a minute
this should help you
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