64post

iTrader: (5)

Your harness needs a powered wire in the crank and run position, you may have check this already? Does it seem to only run when being cranked and dies off when you stop cranking?

lsx68firstgen

iTrader: (22)

Yes I've checked it and moved it to a different power source and it still does the same thing. I'm stumped I've went over everything and can't figure it out. I'm about to rent a scanner now will update in a little while.

lsx68firstgen

iTrader: (22)

Sorry, if I turn the key on and prime the pump it will fire for maybe a second not even. If I don't turn the key off and try cranking again it starts to backfire a little bit threw the intake. But if I turn the key off and prime the pump again it will start for not even a second and I have to keep cycling the key for it not to backfire and fire up.

lsx68firstgen

iTrader: (22)

Didn't get it for some reason.

gagliano7

Sound like you have a fuel problem while running. I bet if you ran a hot wire to the fuel pump for a test it would run.

lsx68firstgen

iTrader: (22)

That actually helped a little. Now it will keep firing for a second but stall without having to cycle the key.

lsx68firstgen

iTrader: (22)

Could it be the map sensor with it being from a 2005 5.3? I forgot to tell the tuner that so I think it's programmed for a ls3 map but not sure.

lsx68firstgen

iTrader: (22)

Forgot I unplugged the map last night and it didn't help

64post

iTrader: (5)

Backfiring through the intake? Could be just a Lean condition or you have some wiring crossed somewhere.

64post

iTrader: (5)

There are a few power sources for the harness, switched, constant (at the starter lug) and cranking.

lsx68firstgen

iTrader: (22)

When I straight wire the fuel pump it will keep firing and stalling with no backfiring. The harness has a ignition wire and one main power wire which both have good power. I'm running the ignition switch wire to the same wire I had hooked up to the msd 6012 when it was carb'd.

tonypaul

iTrader: (2)

its gotta be that saab pedal. I think- unless you change a couple wires on the saab pedal, from what I remember- the ctsv, corvette and 1 one of the monte carlo or impala are the only ones that will work with the gmpp harness...

pmed you~~~~

BoozrCruzr

iTrader: (2)

If you think its the pedal, unplug it. DBW will start without a pedal..., mine will anyways.

laurentj23

iTrader: (27)

I have similar issues with my ls1 swap. Did you replace the cam by any chance and might throw the timing off? How about the crank sensor? Is it new? If you have good fuel and good sparks, you might want to check that issues I mentioned above.

-Siggi-

If it runs on starting fluid then it sounds like a fuel problem.
Check if you have 12v at the injectors.

Also make sure the VATS is disabled.

lsx68firstgen

iTrader: (22)

Thanks for all the quick responses guys but a buddy found the problem. Bad injectors. He stopped by and checked everything out and some aren't clicking he said. Just buy tapping on a few of them the engine would run longer but soon die. I bought them used and have no clue how long they have sat around for. I'm gonna pick up some new ones prolly this week and try again but he swears it's the injectors.

lsx68firstgen

iTrader: (22)

Also when I bought them they had no little plug cover on them so dirt may have gotten into some.

Ant8729

Was wondering if the injectors solved your issue

G Atsma

Hard to say. OP hasn't been here in about a year.