Hey Guys. I searched and didn't really find anything in the realm of what I was looking for.

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 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!

 

I know the bloop sound you speak of, mines made it and not started when some thing wasn't timed correctly. I would be curious to know if the opti is installed correctly?

Reason I say that is because when we did the LS1 PCM on mine and were having issues with the cam position sensor, which from what I have read is used for letting the PCM know what stroke a cylinder is at. But it would crank for ever, until the PCM guessed correct and it started. There was many bloop noises while cranking. I would imagine the LT1 PCM uses the opti to know cylinder stroke position while cranking. So if it was installed wrong, motor wouldn't start because the timing would be completely off. The bloops you hear may be because of that.

 

Yeah I have this nagging doubt in the back of my mind that something is wrong with that Optispark. It was used, but while i had the engine in the shop I opened it up, new Opti cap & rotor, and cleaned the opti pickup sensor. I've done a bunch of them, but that doesn't mean I didn't do something wrong. I'm going to try a couple of things tomorrow then I'll drain it and take a crack at that Opti.

 

Is there a birdnest in your air filter/exhaust pipe? lol