velox65

iTrader: (9)

ok let me rephrase, any way to check the voltage to the pump without a scan tool? no place here in town will scan other than the stealership, besides it wont drive anywhere.

crainholio

iTrader: (2)

Not that I know of, you want to look at system voltage over time and not just snapshot gauge readings.

I scored a used EFILive license and cable on eBay and it's been a great investment for troubleshooting and tuning. Only other way to diagnose these engines without a scanner is to throw parts at it until it's fixed.

velox65

iTrader: (9)

well crap, id hate to have to go through the entire fuel system, a buddy has a tech2 tool, Ill see if I can get him to check voltage for me.

joecar

Find the harness to the pump, unplug it and check the voltage with a DMM (means pulling the tank).

If you have a manifold-referenced FPR (mounted at the fuel rails, with a return line), then om your calibration the IFR table is required to be the same value all across, not sloped like the stock non-referenced FPR from GM (which is in the tank)...

If you can't get the IFR table modified like this, then disconnect the reference hose like crainholio said and cap it off, and adjust the FPR to obtain 58 psi rail pressure.

velox65

iTrader: (9)

Ok I bought a scanner and scanned it, only code it was showing was a "no response from o2 sensor" so I cleared it and she ran like a champ untill this morning when it did it again on my way to work(fml) I'm gonna try and fix the o2 issue and pray that helps