2000 GMC Yukon Replaced torque converter, tranny rebuilt, n

Lets restart

Now truck doesn't start. Turns over fine, but will not start. Never had problems with starting before. Check engine light also on, was not on prior to removal of trans.

When you say doesn't start do you meant it cranks over and refuses to start or just won't crank over at all-I need to know this to continue

park/neutral safety switch. If there's a problem with the NSS the engine w/n crank

Now truck doesn't start. Turns over fine, but will not start-I gave you an answer earlier to determine if its fuel or spark-this is not an easy fix can be a nightmare. I did that so you can give me a direction to start

Installed a rebuilt torque converter, rear main seal, also had the forward clutches in my transmission replaced by a good trans shop.-Replacing these items will not cause a No start problem.

Once again I need to know, does it crank over and refuses to start or won't crank at all/nothing before we can continue-give me something to work with.

Do you hear the fuel pump for 2secs when key is at run position-if so check fuel pressure and report back the readings-if not check fuel pump fuse and fuel pump relay.

If fuel pressure is okay-Disconnect a sparkplug wire or 2 ground it to the engine and have helper crank engine over-do you have spark?

If its a 305 or 350 engine the fuel pressure should be 60-66psi

Also check for injection pulses -use a noid light on the injector/s harness connector-, No pulses no fuel being deliver