Thread: LT1 Engine stopped while running

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Sounds like the Opti-spark distributor has failed. It is behind the water pump and the pump has to be removed to access. Here is a test...
.1 Check the operation of the optical distributor.

2. Disconnect the distributor 4-wire harness connector, then turn the ignition on. On the Powertrain Control Module (PCM) side, check for a 5-volt reference on both the low resolution (Red/Black) and high resolution (Purple/White) signal wires.

3. Verify that there is battery voltage on the Red wire and a ground on the Pink/Black.

4. Plug the connector back in. Check for good square patterns from both the low and high resolution circuits at idle or while cranking the engine. If a lab scope is not available, check for about 1 volt DC during cranking on the low resolution signal and about 2.5 volts DC during cranking on the high resolution signal.


5. If the signals are erratic or flat line 0 or 5 volts, check for bad, chafed wiring to the distributor. If all OK, replace the distributor

The opti spark distributor is bad about the bearing in the base to fail and actually melt the rotor or damage the module. Either way...it would be best to have it towed to a reputable shop and have it diagnosed and repaired there. Rough cost of the opti spark is 400.00 plus install


Btw...if the oil pressure sending unit fails it wil still have fuel pressure......You probably do not have injector pulse