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    Default 93 Blazer 5.7L, rough idle after 2nd or 3rd start to this but here goes... I sometime put info out of order so please read twice if ness.

    problem have been going on for nealy a month now...i am out of work and have very little if no $$ avail, also do not have basic test tools for this problem so all is by observation.

    I can start the Blazer 1st time ea day ( morning/afternoon/evening ) there is slight missing at low rpms but upon accel that goes the problem... I go to a store, come out and a) vehicle starts fine and im on my way..b) vehicle starts but runs rough as *ell and almost dies ( most times this happens, after a 1 min or up to 3 min, it surges and then comes down to a normal idle and away i go). Any starts after the problem has started will always result in the rough idle and gets worse ea time in length before it comes back to life.

    ok, first ill tell you what i have replaced. Fuel filter, plugs, Dist. cap and Rotor, Pcv valve and hose (boot fell apart as i was checking for vaccuum leaks) another part i will mention in next step.

    second is my observations and what i have done so far... removing the air cleaner assy. when it was running rough, i climbed up in carefully and noticed that the drivers side Fuel injector was not supplying fuel (the passenger side was and still always is supplying fuel ). Wiggled the injector connector and it would start supplying fuel (Sometimes this worked and i could make it all the way home other times just for a few min.) got online and went to Chevy talk ( not very fast responces there but 1 that led me to next course of action ) everyone always says your fuel pump is bad and i dont want to rule this out but everything ive read about the fuel pump symptoms, this was not leaning that way ( btw this vehicle had its Fuel pump removed 5-6 yrs ago ). One person said i might have a short in the in the wires from the connector of that injector. I could not safely at the time remove the actual wire from the connector fearing i would break it and then be totally stranded, but looking as best i could inside it looks as if it had abnormal wear on the power node side. I bought a new Connector whip and spliced it on ( yes soldered and heat shrunk). seemed to work ok but i could still wiggle it and get it to fail. tested a cple days and no change. Traced the power wire all the way back to the firewall and could not find any short. So yes i read up on injector failures and sounds as if the wiring (coil) inside the injector can go bad? also noticed that this problem occurs after engine temp (also coolant?) has reached operation norm.

    So at this point the question is: Is the injector bad and if i replace should i replace both? and or does the Coolant Temp sensor have the ability if faulty to only distrup 1 injector?. need help that cost the least $$ since i may be out of work for more months and have no un-employ left.
    Last edited by michaelfriesz; 09-26-2012 at 05:37 PM. Reason: punctuation

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