Old Is New

[erjbsa]

Well I went and did it. I bought an old GM vehicle. It is a '89 GMC C2500 HD 5.7l with Th400 trans and have been going through it to bring it up to road worthiness. So far I have replaced everything I could find that was bad and checked the compression, (150-170) adjusted valves, (running method) but still have some kind of misfire, vibration right about 60-65 mph that has a tendency to disappear above and below that. It also vibrates in park revving the engine. The engine had been replaced about 100k ago and is maybe a '92 or '93 out of a C1500. It was a reman and has a tag to indicate so. Vacuum gauge read O.K. and no mil codes except a code 32 for not having the EGR. The one on the engine is a two wire, the harness has three wires on a four wire plug. I bought a aldl/usb cable and want to read what is going on with the ECM data.
I am hoping I could get some help here. I am a retired guy fixing this truck up to do some traveling/camping.
Thanks,
Eric

[89S10_Project]

Sounds like an interesting project, I've recently transplantyed a similar engine into my 89 S10.

What specific questions might you have?

[erjbsa]

Are these L05 engines prone to leak under the intake manifold?
If the flexplate from the old engine was used on the newer engine could that cause vibration?
Thanks