I have a 98 Bravada 4.3 Vortec that is giving me a hard time. It starts when it wants to, skips a bit as well as loss of power and gas milege...slight smell of fuel. OBD II reader says random misfires on cylinders 1 and 4. Was first told it was fuel issue. Did fuel pump...made no difference...next, the spider...again no difference. Next I was told it was a problem in the head, then told it needed a motor. Any thoughts? (have been told possibly a timing issue or icu issue. I have spare ICU that I tried. made no difference) PLEASE HELP ME!!!!!!!!!!!!!!!!!!!!!!!

Stuck in CT

 

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Have you done a regular tune up consisting of plugs, wires, cap & rotor?

Before jumping to the conclusion of a fuel issue, what testing was done?

 

Yes, have done plugs, wires, cap, rotor, and checked the distributor. Fuel pressure was @ 20 with old pump...@ 60 now with new. As far as tests, I think I know about as much as the garage did...which is next to nothing lol

 

What brand of parts were installed for the tune up? A lot of aftermarket caps & rotors can be bad right out of the box.

 

did u get a code that checked random missfire or did u just check without a light... i have a lot of shaking at idle and i wonder if im doin the same under the hood....

 

My tester only said random misfire yes I have check engine light garage pin pointed cylinders 1 and 4

 

If you used anything other than AC Delco or Delphi for the tune up then that could still be your problem.

I hear NGK is alright for plugs as well

 

i changed the ign coil with one from autozone... a duralast... is that a booboo