YZEATER
1/2 ton status
someone's gotta have one of these on here.
i'm working on a 1997 gmc jimmy/s-10 blazer. it got the 4.3 vortec engine. it started hesitating and not revving up, missing, no power at all unless you barely give it any throttle, then it will go a little bit. you can get it to rev slowly, but if you floor it, it will backfire and miss.
i borrowed a code scanner and it came up p0151, 02 sensor bank 2 low voltage. ok so we replace all 3 02 sensors before the cat convertor. 150k miles and don't really know the maintenence history. take it for a ride same thing. check engine light come on, 02 sensor bank 1 low voltage. i swap out one of the new sensors with an old one, same thing again.
fuel filter looks new, air filter a little dirty, checked for vacuum leaks with starting fluid sprayed around the engine, nothing. no other codes.
so we unplug the mass air flow sensor and the next little sensor in the air intake, and it runs at least 75% better. my other neighbor has a blazer just like it, and try his mass air flow sensor in this one and plug it all back in, same deal, no rev and no power. took apart the throttle position sensor, not much too it and cleaned it, no change.
any ideas?
litte bit more info. it idles rough, after you get it to rev, it will not instantly idle down, it will come down slow. i just thought of this, i have a 96 vortec v6 sitting in my parts area, tonight i think i'll steal some sensors from it and swap them in and out, tps, idle/air control. we pulled 1 spark plug and it looked kinda lean burning, and the gap was .070, spec is .060 . who knows when it had a tune up if ever.
i'm working on a 1997 gmc jimmy/s-10 blazer. it got the 4.3 vortec engine. it started hesitating and not revving up, missing, no power at all unless you barely give it any throttle, then it will go a little bit. you can get it to rev slowly, but if you floor it, it will backfire and miss.
i borrowed a code scanner and it came up p0151, 02 sensor bank 2 low voltage. ok so we replace all 3 02 sensors before the cat convertor. 150k miles and don't really know the maintenence history. take it for a ride same thing. check engine light come on, 02 sensor bank 1 low voltage. i swap out one of the new sensors with an old one, same thing again.
fuel filter looks new, air filter a little dirty, checked for vacuum leaks with starting fluid sprayed around the engine, nothing. no other codes.
so we unplug the mass air flow sensor and the next little sensor in the air intake, and it runs at least 75% better. my other neighbor has a blazer just like it, and try his mass air flow sensor in this one and plug it all back in, same deal, no rev and no power. took apart the throttle position sensor, not much too it and cleaned it, no change.
any ideas?
litte bit more info. it idles rough, after you get it to rev, it will not instantly idle down, it will come down slow. i just thought of this, i have a 96 vortec v6 sitting in my parts area, tonight i think i'll steal some sensors from it and swap them in and out, tps, idle/air control. we pulled 1 spark plug and it looked kinda lean burning, and the gap was .070, spec is .060 . who knows when it had a tune up if ever.
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