Ron-tx

I have a 1988 Chevy Silverado 1500. The 350 V8 needs rebuilding, and until I can do that, I have put a 4.3 V6 in from a 1994 GMC. Started the V6 and ran while in the GMC, so I know it is good.
Now that I have it installed in the Chevy, I cannot get it to start. It turns over and will backfire sometimes, but it never tries to start.

Below is a list of things I have done.

Put a new ESCM for a V6 on it. ( The 1994 did not have it on the engine like the 88 does)
Started with the Throttle Body from the 350 because of the different plug on the Throttle Position Sensor, but have since put the original on and changed the plug.
Replaced the Distributor Control Module
Installed New Distributor Cap, Rotor and Wires
Replaced Spark Plugs
Traced the routing of the wires multiple times.
Verified Spark on each plug.
Check TDC multiple times.
Tried priming the throttle body even though Gas was getting to it when I swapped them.
Checked the injector wires with a “noid” light. It blinked as it should.
I was going to replace the Engine Control module with the '94, but the plugs are different. (The computer in behind the Glove Box.)

Does anyone have any suggestions that I should try?
Thanks,

Chevy lover for life

If it does not have the proper fuel pressure and the proper fuel volume - it will not run.

I did the same thing to a 1988 Chevrolet Astro Van.

I put 3 fuel pumps in the tank and could not get it to run because there was a obstruction in the fuel line.

You could dribble fuel in the throttle body and it would run and back fire and catch the can of gas on fire, but it would not run once you got it to run by dribbling fuel into the engine.

Either rebuild the other engine, remove the fuel injection and convert to carburetor and use a regular old fuel pump, or get the fuel pump in the tank to work or it won't run. You can check the filter - but I never saw one that plugged up so bad that it wouldn't run.

2wd-K5

i would check the fuel pressure and fuel volume first, after that, i have a question, are you sure you have the distributor set right?

desrtrat

are the V6 and V8 wiring harness the same? are they interchangeable? you may need to get the V6 harness and install it..

good luck

Ron-tx

Want to thank everyone for their suggestions. I've been working on it for a few days, and it was the distributor and a dirty fuel filter. I never turned the distributor using a wrench, but when I was loading the engine to bring it home, it rolled away from me and I couldn't stop it before it bumped the distributor. I thought it just cracked the cap which I was going to replace anyway, but I guess it turned the distributor also. Checked the fuel pressure at the TBI, and it was 0. Checked it behind the fuel filter, and it was 10 - 12 PSI. Changed the fuel filter, and the pressure at the TBI went up to 10 - 12 PSI. Cranked it up, and all I have to do tomorrow is fine tune the timing.
Thanks again for all your suggestions. It really helps to get other opinions.

2wd-K5

no prob man, always nice to have a cool head brought into the repair, kinda funny how i hit both on the nail lol, i would have thought 1 or the other

Eherm1

I replaced the fuel pump,fuel filter and finally the fuel pressure regulator under the plenum on my 2000 Chevy Blazer 4.3 and the fuel pressure regulator was the hard start,no start problem.After that I replaced fuel injector spider and it's never run better.