GWTFI

I've built a Hummer H1 clone (a rock crawler for lack of a better term) and I used a LT1 and 4L60E out of a 1995 Camaro to power it. I went thru both the engine and transmission back in 2005/6 and they are fresh builds. Both are mostly stock except that the LT1 has springs and a Crane 227 cam. The ENTIRE thing has been sitting in storage since 2006.

I don't have a lot of my programming tools/etc from back in the day, but I have a few streetrod bins I did back then, with no emissions/vats, etc. So I wire it up and plumb it and the damn thing and it won't fire. I have spark (checked with a spark tester), I have injector pulse and gas flow (rail is pressurized and I pulled the rail up to watch the injectors squirt). But it simply will not fire.

I've tried starter fluid, endless cranking, flood control with the pedal down, nada, zip, zilch. I get some ignition, but I also get a weird misfire, I can only describe it as a sort of 'BLOOP'. I implicitly trust the machine shop that did the work, they've built several LT1s for me for C&D's "One Lap of America" and they know the LTx/LSx platform well. But I suppose it could be a tooth (or more) out of timing.

I'm no EFI babe in the woods but this has me REALLY stumped. Help, prayers, thoughts? ? ? ?

Thanks guys!

z28camaro1996

iTrader: (1)

the lt1 has to have at least 43#'s of fuel pressure.

LT1

iTrader: (1)

Have you checked PCM ground?

Adam96z

iTrader: (1)

A bad opti will sometimes backfire out the intake and "bloop" if it is going out. I had the same problem.

mrchyzy16

iTrader: (1)

pics of said hummer or ban!....lol j/p..I would like to see it tho.

deerslayinrednek

iTrader: (8)

is it possible that the that the opti wasnt lined up correctly when it was installed?