[FadingAurora]

I have an 02 S10 4.3 4x4 with 170k miles that will not start.
The issue started with it randomly stalling while driving, not sputtering either like I turned the key off. I pulled it home and it had no codes or security light, The fuel pump had been replaced with a cheapo so we figured that was the issue. I purchased a new fuel pump and put it in and it fired right up and then stalled after a minute. After replacing the fuel filter it had the same issue. Eventually it started only cranking and the pump wasn’t turning on. I ran power to the pump from another power source and it worked fine. So I powered the pump independently and still only cranking. I could get it to run if I kept spraying starter fluid and the coil was fine. When chasing wires I noticed that my ecm had some major corrosion around the bottom when I removed it from the bracket so after checking the harness for faults I ordered a new ecm. When I got the computer I installed it and re learned my key and it worked fine. When I went to start it again only cranking but it had the p1336 engine code for the ckp re learn. How is the relearn procedure supposed to be done without it running? Should I replace the ckp sensor?

 

[FadingAurora]

I forgot to mention that the pump still won’t turn on.

 

[KJF95S-10]

I wouldn't bother changing the PCM, that's usually never the issue. Put the old one back in just to rule the new one out. New PCM should have VATS active anyway and won't allow your truck to run for more than a couple seconds. 9/10 times any issues on these later 4.3's is related to a failing plastic distributor or a failing injector spider. They don't have many other issues. Start by replacing the distributor as they are cheap. Try a different crank sensor as well. If that's not it pull the upper intake off to check the spider.

 

[bk2life]

I could get it to run if I kept spraying starter fluid

well then you dont the crank relearn, you have a fuel issue. Tiem to do some research and figure out whats cuasing no fuel. First, like stated, put your old ocmputer back in, and then go get a fuel pressure checker from autozone. Its free. and test your fuel psi. Then follow the flow chart to figure out the issue from there. OR it might be easier to have your truck towed to a shop and pay the $1500 bucks to have it fixed.

 

[Anna]

Have you checked the fuel pump relay?

 

[oldeerslayer]

More than likely the fuel pump is either not grounded properly back under the tail lights or you got a bad pump.

 

[FadingAurora]

Have you checked the fuel pump relay?

Yes I have checked the relay and the wiring for the pump it all checks out, when I clear the p1336 code the pump kicks on for a split second and shuts off as soon as it re appears. tomorrow morning I’m going to replace the crank position sensor and see if anything changes