Timing Changes

[procharge94]

Is there any way that the timing could have changed on a motor from the time it was removed from a car to swap oil pans, to the time it was plugged back into the harness? This entire time the distributor was still in place on the block. The motor was on an engine stand and rotated upside down for the swap. When the motor was removed everything ran fine and the car was driven into the garage under its own power. Now, when I turn the key, the idle won't keep itself alive, and the only way to get any sign of life is to feather the gas pedal, which by the way reacts incredibly delayed. I will push the throttle, let off, then a few seconds later the motor will rev a few thousand rpm's. The 30 seconds I was able to feather the throttle enough to get an idle, the idle was at 700 rpm and was poping(small backfires) continuously.

The motor in question is a 302 from a 1994 GT. No a/c, no egr, no smog pump. I removed the vacuum tree; could I have missed something with the vacuum lines? The only vacuum line I have is the line from the brake booster to the back of the upper plenum. Well, that and the small line that runs to the fuel pressure regulator.

I'm not quite sure what to think. It sounds and acts as if the timing has been backed way down, but I don't see how this could have occured considering the distributor never came out of the block.

Would a tear in the gasket that fits between the upper and lower plenums cause this erratic behavior?

Am I chasing a gremlin here that is just simple user error? I feel like the shortbus will be pulling up any minute now to take me to school.

[forcefedlx]

Check the tps it might not be plugged in, if it is ishould show .90 or close at key on engine off closed throttle position ,and somewhere above 4.8 at WOT. measure voltage between orange and the green wires

[procharge94]

I'm a bit embarrassed to admit this, but I located my problem. The upper and lower plenums were leaking at the base. A new gasket and proper torque fixed the issue, for now...