1985 GMC Blazer help!!!
Lacklustzero
05-24-2004, 08:55 PM
My 1985 4x4 blazer runs fine......until the "Service Engine Soon" light comes on, then it idles like crap and will eventually just shut off.
Then I'll turn the key to off, then start it back up....the light is no longer on and my blazer runs fine again. But eventually the light will come back on and the cycle continues. The motor is not the stock motor. It's a V8, 305, throttle body injected, I think it's out of a '92 Chevy. I changed the plugs, wires, air filter, fuel filter, dumped injector cleaner in the tank, brand new fluids all around (tranny, oil, differentials, transfer case). All cylinders are firing.
What could it be?? A computer issue? why does the light come on and off again?? It runs fine when the light is Not on. Only when the light comes on is it a problem. Any help would be much appreciated. Thanks
Then I'll turn the key to off, then start it back up....the light is no longer on and my blazer runs fine again. But eventually the light will come back on and the cycle continues. The motor is not the stock motor. It's a V8, 305, throttle body injected, I think it's out of a '92 Chevy. I changed the plugs, wires, air filter, fuel filter, dumped injector cleaner in the tank, brand new fluids all around (tranny, oil, differentials, transfer case). All cylinders are firing.
What could it be?? A computer issue? why does the light come on and off again?? It runs fine when the light is Not on. Only when the light comes on is it a problem. Any help would be much appreciated. Thanks
Blazing Rice
05-24-2004, 10:42 PM
EGR valve? Those things are the devil. I imagine it's somewhere on your valve cover. :smile:
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