I know this isn't a Camaro specifically but since it's electronics are the same it would be worth a post, perhaps the electrical guru's out there could lend me some advice.

I'm currently a second year auto student and this is an instructors truck he's asked me to help him with. It's an 85' Sanoma with a TPI V8 conversion utilizing an '86 5.0 engine and drivetrain. The vehicle has driving 80k with no problems until one day it started harshly bucking the starter (almost like the motor tried to fire backwards while cranking) my instructor was able to get it started and drove it for a few days - the problem got progressively worse ruining two starter gears and one ring gear while he was trying to diagnose the problem. He said he thought it was throwing a code 43 before he finally gave up. He said he had changed the distributor,checked the timing like ten times over, changed ignition control module, ecm and even used a different prom (apparently he had a buddy burn custom proms using a moates adaptor) Now before he suicides some more parts he'd like to find out once and for all just what is causing the problem from what he describes it's almost as if it's hunting for the right cylinder or cycle to start on and it's hitting the wrong one.

Another thing to note is that he said he discovered a burnt relay and adjoinging wires and replaced the unit and the wiring to it. I later discovered that this was a MAF power relay and that the E pin was visably burned inside it does seem to still function however as far as I can tell. Scanning through some of these posts I already checked a few things out as i'm going through all the wiring anyway on the MAF sensor itself I checked the grounds pins A and B both are good with .005 ohms or less of resistance. (I have the rest of my results written down elsewhere I'll have to find them) The fuel pump is priming with the key on, as there is fuel in the rails and you can hear it prime when you turn the key indicating the MAF should get power if I'm not mistaken. Unfortunately I cannot yet try to start the vehicle because the starter and ring gear are both toast so again I'd like to figure out the problem before I replace them.

Any advice or direction would be greatly appreciated as my brain is turning to mush ^_^

 

I don't know of an electrical problem that would cause the types of damage your describing. I would look for a mechanical problem like the timing chain jumping and the valves smacking the pistons. Pull a valve cover off and check for bent pushrods or broken rockerarms.

 

I guess I could give that a shot honestly I'm running out of ideas, I can't see how ALL those problems can be simultaneously related either. I was considering pulling the valve covers off to at least assure myself of valve position in relation to TDC. I'll check it out Monday before class and if I find any juicy carnage I'll be sure to post it.

 

Just an update on what I thought was an electrical problem.

Even though my instructor swore up and down that the timing was spot on and he replaced the dizzy and ignition module. I decided to recheck the timing position and firing order since I could not find any obvious faults with any of the other electrical components or the ecm.

For this application it was easiest to turn the motor with a flywheel turining tool from back of the motor. First I turned to tdc, then checked the distributor and I was on the wrong stroke, so I kept turning to one more revolution and then the thing met with resistance and halted. I went ahead and turned the motor back the other way (backwards) and seeing if I could get it on tdc and about one turn later the same thing happened. With a considerable force you could push past this hard spot but something is definitely hitting. ( Might explain the chewed up starter and ring gear!) As far as I could tell the flywheel and flexplate were still turning at the same rate with each other which probably rules out broken crankshaft. But the resistance is on every single turn (360 degrees) which suggests to me that it's in the lower end.

Today I began stripping down the motor for removal - this ones goin to be a peach to pull. :-/ Just for sh*ts and giggles I pulled the timing cover but it doesn't appear to have skipped time, but the timing chain seemed a little looser than I'd expect out of a motor that only had 80k on it.