Need help, Engine suddenly began very loud knocking & tapping

[Ski Bum]

Ok, so the ECU in my car (91 GSX) has basically been sitting on the passenger seat for a while as I've been giving the car a full overhaul. The car drives fine, has good power and a host of new parts installed. Today I decided that it was time to mount the ECU back where it belongs and tuck the wiring harness away. While doing this I noticed that the wiring harness near the ECU plugs had been opened up and a few wires looked like they had been spliced, etc, hack job.... I positioned the wiring and ECU behind the console and mounted the ECU in place. Afterwards I start the car and now it sounds like there is no oil in the engine at all! The oil level is fine, no leaks. The sound is like a severely knocking rod or heavy valve tap, I'm not really sure.

Could I have inadvertently pulled a wire out of the ECU that controls whatever is causing this? I'm afraid to even start the motor any more for fear of throwing a rod or worse.

Please help, thank you.

 

[Ski Bum]

Ok, so I just pulled out the ECU, sort of working in reverse of what I did earlier and the wiring all seems to be intact. However I am now getting a clicking coming from the ECU or that little unit mounted on the passenger side of the HVAC console frame. It clicks when I turn the key to on and off. Isn't that a sign of a fried ECU? I hope noe because I just replaced the ECU a month ago.

I wanted to add that during the short period I ran the engine there were no cel's, maybe it couldnt run long enough for one to appear but I wasnt about to let in run the way it was for much longer.

 

[Ski Bum]

I just pulled the wires and cranked the engine, everything fine. Next i pulled the plugs and cranked the engine, fine. Without combustion the engine turns over smoothly. just a month ago a compression check yielded 152psi on all cylinders.

What is going on?

 

[Ski Bum]

Ok, did another test. I have another ECU that had some problems but still was able to run the car just with a few functions removed. Using that ECU the same thing happens. The car starts then stumbles terribly along with a metal on metal tapping that sounds like severe valvle tap or what a motor may sound like running with no oil.

So the original ECU should be ok if the same thing happens. My guess is that I shorted somethign causing the engine to run this way.

Any help whatsoever is appreciated.

 

[Ski Bum]

I wanted to add that yesturday I installed a turbo xs dual stage manual boost controler. With my mods I'm only using the single stage set to about 14-15 psi. During the adjustment phase the boost spiked a couple times to 18psi but only for a split second. I got the mbc set and the car ran great, no problems.

Not sure if this could be related, hope it isnt.

Edit: I Heres a list of my mods since I cant seem to be able to make any changes to my profile so you know what else is on my car.

2.5" TBE with stock cat
P&P 02 housing
P&P 14B (exhaust housing inlet only)
EVO GT exhaust manifold
1 step colder NGK's
hacked airbox and MAF
shortened I/C hoses
EGR blockoff plate
blocked vacuum lines on throttle body
turbo xs MBC

Aside from that I have replaced many of the factory parts with new ones.

 

[Talesin]

If the ECU harness is skrod, then there's any number of things it could be doing... advancing/retarding the timing severely, crossed signals, and so on. Or it could be screwy sensors feeding the wrong info to the ECU.
Also, the 'edit' function is usually sitting there... rather than re-re-re-reposting.

 

[Ski Bum]

Assuming everything is ok mechanically and the problem was caused from crossed wires, etc is it safe to run the motor while attempting to fix?