I wasn't aware that the Tahoe forum had moved, so I am moving my 99 Tahoe problem, (I hope with the admin blessing ) from the generic GM forum.
It has been a while since I posted this question. Since then the Tahoe forum is gone, so I am reposting it. I had my 1999 5.7l Vortec rebuilt after 157K and a spun bearing. I have tried numerous ways to set the timing and either the car runs as if it's fighting itself or has no power at all. I also sometimes get an error code when I adjust the distributer, that there is a mismatch between timing. P1354 CPS and DIST mismatch.
While parusing other GM forums I noticed that at least with the 3.1l engine there is a plug that must be disconnected to set base timing. Is there such a thing on my 99?

You must get a scanner on it, the rotor is slightly out of phase with the dist cap contact for #1, the actual timing is not adjutable, you are synchronizing the cam sensor to the crank sensor, a scanner with the proper functions is required here to get this setting as close to 0 as possible.

Am I stuck going to a GM dealer or will a Snap-on scanner do it?

Am I stuck going to a GM dealer or will a Snap-on scanner do it?

If you have the GM cartiage for that year a old MT snappie will do it.
A tip on doing it is to raise the RPM over 1000 rpm for the scanner to adjust to the new setting.
MT

The base timing on a vortec 5.7 is 2 degrees +/- cam retard mine is set at 0 runs good, you do need a scanner that can read data on top of codes.

The base timing on a vortec 5.7 is 2 degrees +/- cam retard mine is set at 0 runs good, you do need a scanner that can read data on top of codes.

Better get out your repair maual and do some reading.:grinyes: :rofl: :lol:
Base timing is set by the crankshaft sensor and controled by the VCM.
Cam retard setting has nothing to do with the timing.
You can turn the dist all day and not change the timing.
MT