ls3 swap won't start! Pulling my hair out!
#1
ls3 swap won't start! Pulling my hair out!
Ok, so I've swapped a ls3 into a 68 camaro using the gmpp standalone harness with my own ecu o had base tuned. I turn the key to the on position let the fuel pump prime and turn the key it starts but for maybe a second not even. If I keep cranking it starts to backfire a little not much threw the intake. If I turn the key off and back on it will do the same thing, start for a half a second and stall. I'm stumped. I've tried 2 different ecu. Anybody have a suggestion on what it might be? I havnt scanned for codes yet as I have to rent and I am going to most likely tomorrow but just though I'd try here to see if anyone could help. Thanks for any help.
#3
VATS first and then do you have a good spark if VATS is ok. Make sure the ground wires for the coils have a good ground. I have seen cars actually run somewhat with the ground wire disconnected. Same for the injectors. Double check the ground and power wires.
#4
Yup vats is turned off. I have checked grounds, power supply, literally un-loomed my harness the other day looking for broken wires ect. Could it be the map sensor? I'm using a map from a 2005 5.3 with a gmpp 58x ls2 standalone harness. But now that I think about it I don't think I told the tuner that.
Trending Topics
#12
TECH Regular
iTrader: (2)
Join Date: Dec 2009
Location: Austin Texas
Posts: 414
Likes: 0
Received 0 Likes
on
0 Posts
your right, no iac for dbw... i was thinking you had dbc...
I have heard of stand alone harness' having wiring errors. I remember reading something about the wiring on some electronic gas pedals being different. Maybe worth looking into.
Where did the electronic gas pedal come from?
I have heard of stand alone harness' having wiring errors. I remember reading something about the wiring on some electronic gas pedals being different. Maybe worth looking into.
Where did the electronic gas pedal come from?
#16
No I have not checked the pressure at the rail as I'm using holley rails with a/n fittings and don't know how to go about it. I did crack a line before I ever tried starting it to see if fuel was flowing and their was alot of pressure. But it might be worth checking out thanks.
#17
TECH Regular
iTrader: (2)
Join Date: Dec 2009
Location: Austin Texas
Posts: 414
Likes: 0
Received 0 Likes
on
0 Posts
are you able to check for codes? I also remember something about that you have to have an approved throttle body part number for the gmpp harness and the aproved part numbers are in the book that came with harnesss...??? something like that..
I looked into the gmpp stand alone harness' awhile back but decided to go a different route..
I looked into the gmpp stand alone harness' awhile back but decided to go a different route..