I have a 94 B2300 5 spd. Motor has been rebuilt, after assembled has a high pitched squeal. Not sure what it could be. It doesnt seem to affect the performance of the motor but is extremely loud and annoying. I can literally feel the sound when touching the valve cover. I suspect it could be a vacuum leak but not sure how to test it properly. I know a leak down test checks for leaks but I dont have the tools. Other than the sound it has been idleing very high. Ive read the tps coulf do this and I'm replacing it tomorrow. At the same time my oil pressure started to spike. At first it was fine, within the last few week's its been getting higher and higher. The motor runs great just cant figure out whats wrong. It does throw a code but I have obd 1 and use a wire to flash the code, unforchunently the code always vanishes when I go to read it.
New Parts: Piston rings, gaskets all around, icm, psps, egr, iac, plugs and wires. Ive nearly replaced everything on this truck thats just what ive done on the motor. A different motor will be going in eventually but I need it for a daily so any suggestions are welcomed.