P0336 with 383 build

[HoP]

I put this up over at LS1 tech.

Customer brought me in a 01 corvette ls1 383. It ran fine with the factory motor but he broke a piston to boost. A shop in northern ca built a 383 for him and ever since it runs like crap. Will not rev above 1500 rpm's, black smoke, exhaust egt's are going through the roof after a few minutes of running, and cylinders 1 & 6 have no injector pulse.

I pulled down the lower sump to inspect for the correct 24t reluctor and to also make sure it was not installed backwards. I checked the visual straightness of the reluctor and verified that it has an uninterrupted signal back to the ecu.

All three wire leads ( 12v, low reference, and signal ) or perfect back to ecu.

I checked the tune and it is fine. The intake track is not blocked by any foreign obstruction. I disconnected the exhaust at the manifolds and it still has the same condition. It runs as if the spark is extremely retarded but according to the scanner it's 16* at idle around 113F.

I'm leaning towards an improperly indexed reluctor. Could this be causing the issue? Thanks for taking the time to read this and any replies are most welcomed.

Thanks

[WS6FirebirdTA00]

Have you tried case learn? I assume if it won't rev past 1500 you can't do that.

I wonder if this is causing the injectors not to fire on the other cylinders. Do you have a log of this? I don't recall coming across any issues like this so I can't really provide much in the way of educated suggestions.

[HoP]

Case learn is not possible, I can't even let the car come to the temp. I'll post a log tomorrow morning. Thanks

[Ben Charles]

Seen a reluctor on backward before cause similiar issues, pull the cover.


EDIT, just seen you verified its not on backwards

[JamesLinder]

Are you absolutely certain you have the "correct" reluctor? I have read where installing the wrong one will do this; I have no personal experience with this however, thank God.

[HoP]

Pulled the timing chain cover and verified proper cam timing.

With the sump pan down again I was closely looking at the reluctor wheel and I can see a spot where the machine shop drilled the counter weight for balancing, they touched the reluctor wheel a little bit. Unfortunately without removing the crankshaft I can not tell if the reluctor wheel is indexed correctly.

But the question remains. Obviously there is a reason to index the reluctor wheel to tdc. So if the reluctor wheel is indexed correctly it would have to throw the ecu's timing off either advanced or retarded.

[JamesLinder]

correct! Just curious, is it possible to put the reluctor on incorrectly? This would be a disaster if you have to pull the crank!
I do know for a fact that there are 2 or 3 different reluctors and that you MUST use the right one for your engine. Not sure
what the difference is, whether it has to match the PCM or the crankshafts are different.