Bobrob

Help me - engine cranks but will not start!

We have tried and tested everything on this car and all seams fine. We have fuel pressure, signals on injectors, good sparks on every sparkplug (15 mm lenght of sparks and no error codes using CCM Code Reading (only got three dashes in section 4.1).

Engine stopped suddenly and could not start again. Sparkplugs were dark and oily. They are changed for new, BUT engine will not event start on ether starting gas.

As we get a good spark we don't think the OptiSparc is bad.

Could problems with ECM cause spark timing problems?

Car is a 1992 LT1.

What is the problem?

sailorsteve

It seens likely a timing issue. Possibly the rotor in the opti is the problem, and has shifted out of position. Could also be a problem with the ECM, which controls timimg.

0Paul Ruggeri

Have you checked the compression?

Bobrob

Yes, looks like we found the problem here! We just checked timing of spark and it's 90 degrees off - actually when #4 is in TDC the spark spark goes to cylinder #8, so the OptiSparc must have a mechanical problem - axel or rotor has moved 90 degrees off!?

Thanks for your support! We will be back with some additional info as soon as we removed the OptiSparc and let you know!

Bobrob

Bobrob

Yes, we have good compresson and valves are moving - timing chain should be ok.

Bobrob

Yes, finally we found the problem as we today removed the ols Opti-Spark and took it apart.

The bearing for the rotor had overheated, so the plastic melted and the two srews that holds it in position had moved - in the plastic - to a 45 degree offset.

Now we will just clean everyting up and install a new MSD vented Opti-Spark.

Robert

orenkrief

hi i have the same problem . but on my 92 it will start in the morning with the gas pedal but after a drive it can shut off and wont start until evening .did it hapend to your 92 as well??