Won't start (after fuel pump replacement) 92 rs 305tbi
Won't start (after fuel pump replacement) 92 rs 305tbi
Well I'll tell you this, I'm not a big mechanic, but I'm going to do the best I can to get it up and running and explaining everything. Well it all started the other day. I go into a store real quick and I'm back outside within 3 minutes, put my stuff in my back seat. Go to start it up and it cranks, and cranks. So I turn it off and take the key out again and try again. I was thinking maybe I need a jump so I have a friend come give me a jump. Still nothing, we take off the filter and such and we can't smell any gas, one of the guys take a screw driver and open up one of the butterfly valves and doesn't see any gas squirting or anything when I try to crank it. Got it towed back to my apartment the next day. Had another friend of mine come take a look at it, and we all decided it's my fuel pump since we couldn't hear it pressurize or whatever. So change that out, which was a bitch imo compared to the cars I've owned before. Still nothing. It is completely dark out so we can't see much, we take my volt meter and check the plug to the fuel pump and we go a reading of around 4-9 on however he did it. Then tried it with the pumps wires connected and tried it as close to the pump as possible on the wires and only got a reading of 5ish. Still no pressurizing. We check all my fuses and they are all good. He connects it to I think was the big yellow wire under my dash and go a reading with my key turned on, so I'm thinking it's not the VATS since it is trying to crank, battery is good. Tomorrow we are going to try to jump from that wire to my fuel pump. Might also go pick up a fuel pump relay since they are cheap. Does anyone have any clue on what I should check/do. I really need my car up and running asap. I can't afford to get rides to and from work. **** I could hardly do this camaro as a DD with it's 20-25mpg.
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Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
Re: Won't start (after fuel pump replacement) 92 rs 305tbi
hi there
how about trying this if you havent already?
place the key siwtch in the run postion for about 10 or 12 minutes this resets the security system when it faults and therefore will not allow the engine to start/run
clean the ign key lock cylinder out real good with some brake cleaner and compressed air, or other cleaner that will dissolve grease dirt grime gunk
the sensor in the switch over time gets grease and dirt on it and it cant read the key/resistor
this worked for my brothers bonneville
every about 6 or 8 starts it would fail and he would have to lreave the key in run position til the light went out then it would fire up
cleaning with the cleaner solved the issue
and this was last spring
and its still doing fine now
a fule pressure test would have told you if FP was ok or not so you wouldnt waste time and work and $ on another FP that was not needed
a spark test with a spark plug on a plug wire would tell you if you have good correct strength of white or blue spark
sometimes the FP wire the light gray one that runs down the body from the relay and oil switch on the engine will die lose voltage somewhere along the body for some unknown reason and therefore be weak or no voltage to the pump
have seen it happen and had to repair this on many vehicles over the years
it happens alot on the S10 trucks and blazers 1980s and 1990s
and some other vehicles
if yours has the older style wiring harness in it you can jump the gray and orange wires and it will run the FP. at either the FP relay or at the oil switch on the engine
orange is full time hot it also was ECM power feed circuit wire
there is a fuse on pass side fender in about the middle of length of it, or should be anyways
it is enclosed in a black small housing just for the fuse itself, alone
its for the FP
but im not sure if 92 had this still
i know the '88 and such years had this though
check for hot at fuel injectors
they should be hot with key in run position, they all splice totgether run from same power source/circuit
the second wire to injectors is signal from ECM and is ground side, from ECM, each injector has its very own ground signal wire from the ECM
in most fuel system types anyways
how about trying this if you havent already?
place the key siwtch in the run postion for about 10 or 12 minutes this resets the security system when it faults and therefore will not allow the engine to start/run
clean the ign key lock cylinder out real good with some brake cleaner and compressed air, or other cleaner that will dissolve grease dirt grime gunk
the sensor in the switch over time gets grease and dirt on it and it cant read the key/resistor
this worked for my brothers bonneville
every about 6 or 8 starts it would fail and he would have to lreave the key in run position til the light went out then it would fire up
cleaning with the cleaner solved the issue
and this was last spring
and its still doing fine now
a fule pressure test would have told you if FP was ok or not so you wouldnt waste time and work and $ on another FP that was not needed
a spark test with a spark plug on a plug wire would tell you if you have good correct strength of white or blue spark
sometimes the FP wire the light gray one that runs down the body from the relay and oil switch on the engine will die lose voltage somewhere along the body for some unknown reason and therefore be weak or no voltage to the pump
have seen it happen and had to repair this on many vehicles over the years
it happens alot on the S10 trucks and blazers 1980s and 1990s
and some other vehicles
if yours has the older style wiring harness in it you can jump the gray and orange wires and it will run the FP. at either the FP relay or at the oil switch on the engine
orange is full time hot it also was ECM power feed circuit wire
there is a fuse on pass side fender in about the middle of length of it, or should be anyways
it is enclosed in a black small housing just for the fuse itself, alone
its for the FP
but im not sure if 92 had this still
i know the '88 and such years had this though
check for hot at fuel injectors
they should be hot with key in run position, they all splice totgether run from same power source/circuit
the second wire to injectors is signal from ECM and is ground side, from ECM, each injector has its very own ground signal wire from the ECM
in most fuel system types anyways
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theshackle
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Mar 5, 2017 06:37 PM





