Replaced my VSS with brand new one, exact replacement part. And now I have a code 42 VSS signal noise. WTF?:smokin:

TBI?
TPI?
What year?
more info...

That would help wouldn't it? 88 k5 TBI 350, VSS is behind the dash. Motor is stock with the 7747 ecu.

DTC 42 is set when one of these two conditions exists: "If the bypass line is open or grounded, the ignition module will not switch to IC mode so the IC voltage will be low and DTC 42 will be set. If the IC line is grounded, the ignition module will switch to IC, but because the line is grounded there will be no IC signal. A DTC 42 will be set."
DTC 42 has nothing to do with VSS. Check your wiring, especially the IC Bypass ckt going from the ECM pin B2 (Tan/Black wire), to "set timing" connector, to pin B of the ignition module (a 4-pin connector on the distributor).

Man thats a huge shove in the right direction, thanks. Now am I looking for 12 volts or do I need my ohm meter. I case you haven't guessed this is a new one to me.

Code 42 will set if you disconnect the esc wire to time the vehicle, and fail to disconnect the battery to clear the code when finished. However, it will not carry an SES light on! With the light on, and pulling code 42 there is an open in the circuit. See if this helps:
http://www.chevythunder.com/est_code_42.htm

Ok, cleared the code. Idled the engine, checked for codes. None present. Drove it and under a slight load, now starts bogging down again. I'm leaning toward a fuel pressure issue now.:smokin:

I am betting it is your piston return springs are bad. You can gaet them here.http://kalecoauto.com/index.php?main_page=product_info&cPath=3&products_id=27