Hello All. I am new to the board and I am looking for some help in the form of advice. I have a 1995 Z28 with 75,000 miles. I chose to make the final push to finish my multi year dream project (detailed below if you're interested) this spring with a freshly built 383 LT1.

The problem is I finished the 500 mile break-in and put about another 500 miles on the 383. It was running better each day. I was even ready to take it to the local dragstrip to shake it down when I had an engine fire. Spark plug wire on the header and a yet to be fully understood fuel leak. Fortunately the fire was put out in 1-2min., destroying the wiring, fuel lines, a couple of injectors were blistered, and some cosmetic parts under the hood (cowl, wheatherstripping, retainers for the isulation under the hood).

I have replaced the cooked wiring harness with a good used one, new fuel lines and injectors, seals, etc.

Now I have a cranking engine with no injector pulse. I have checked all of the fuses, verified spark at the coil and plugs, reset the PCM by pulling the U/H and I/P fuses, ohmed out the harness, verified 12vdc at the injectors, double/triple checked the PCM grounds and 12vdc, verified all the sensors associated with the PCM, ohmed and or verified VDC at the ALDL connector. I jumpered a quality scanner OBDI/II (Innove Iequus 3120) according to the instuction provided by www.shbox.com (man I owe shbox and intend to donate) and have no communication with the PCM.

I want to be diligent in the troubleshooting but without DTCs to work with I am stuck. I beleive I have covered everything and think it is either a problem with the Low Resolution signal from the OptiSpark or the PCM was fried in the fire.

The optispark is new and was not visibly effected by the fire which was extinguished with a dry/powder type extinguisher, but it also appears everything else controlled by the PCM is functioning (fuel pump, MAF and MAP reference voltage, SES, even the Security/Anti-Theft was activated some how during one session of troubleshooting).

I have an ALDL/USB on order with www.Moates.net and FreeScan (and TTS ScanMaster) are up and running on my laptop. I just need the cable but I suspect that I will have the same results as with the Iequus 3120.

Does anyone know how else I could troubleshoot the PCM (or some other symptom I should look for) or is it time to buy one and see where it goes from here?

Thanks in advance!

The rest of the story:

In the past few years I have upgraded the suspension to all CM Tubing including UMI Performance rear control arms, panhard, torque arm, front upper a-arms, Vrogland (sp?) springs (1.25" lowering), AGX adjustable shocks, polished 18" zo6 wheels, slotted and vented brakes, SS brake lines, Vredstien ZR rated tires, SLP CAI, Oversized TB (52mm I think), Pacesetter shorties, updated the B-W m6 with steel shift forks and Pro 5.0 shifter, Al. flywheel, Al. driveshaft etc... . I kept the internal engine components stock for fear of causing reliability problems, LOL!

Unfortunately I broke the oil cooler/filter adaptor and siezed the motor when I had a brief encounter with a patch of gravel on a dead end road. No damage other than the siezed motor. It sat for quite a while becuase of the frustration.

I lucked out when I replaced the original motor. I baught a salvave replacement to get me by while I overhauled the original. While inspecting the replacement motor it turn out to be a factory 4-bolt (yea). The 4-bolt ran fine for stock so I kept it in place. This spring I chose to upgrade to a 383. I had done a quick, stock overhual on the 2-bolt. I swapped the motors to build a 4 bolt 383. That is about when the real stuff started hitting the fan. Broke the 2-bolt motor (oil pump/pick-up failure). The shop I use is very reputable. The shop I used for the new motor is very close to home (I live in the out away from the city). They really specializes in High CID, NA and nitrous Pro Drag racing motors and the 383 ran over budget. Eagle forged crank, Mahl coated pistons, Eagle H-beam rods, Comp Cams K-Kit (cam, roller lifters, springs and retainers), Comp Cams Al. 1:1.6 roller rockers, Manley hardened push rods, ported/polished factory heads, street/strip oil pan and matching pick-up, MSD OptiSpark, MSD 8.5mm plug wires, SPEC Stage 3 clutch ......the hole 9 yards. While the car was down I replaced the K-member with a tubular K-member with matching lower A-arms. I have probably forgotten some of the upgrades.

I think the fuel fed fire was the result of a bad seal (it sat a while as I mentioned) in the original factory quick connect or the fuel regulator. Forunately it was rush hour and a local utility company service truck was close behind and extiguished the fire before there was much damage beyond the wiring harness and fuel lines. I was sick, sick, sick and it was plain old painful to see. Clearly at this point I have spent more than I should have but I am committed to finish and move on.