crank no start issue

[nickhinton]

I need some help guys, I just built my 355 over the winter, got the car fired up and it sounded like it was running great. Long story short I got code 36 High res failure from my new msd optispark.. Well I ordered a new one from autozone, got it installed today and same issue. The car cranks and cranks but acts as if there is no spark. The ICM tested good, as well as the coil. I have spark if i hold the coil wire to a ground and the same with the individual plug wires. When I watch data on my scan tool it is not displaying rpm on the scanner, every once in a great great while (every 5th round of cranking or so) the car will cough once like its trying to roll over and it will display rpm for that split second and go right back away. The only things that have changed since the car ran was two new 02 sensors.. Any ideas fellas? at this point I may have to consider taking it in, im out of ideas on where to look. thanks guys

[englundjd]

get a good ACDelco opti not an autozone unit. ACDelco is the only known reliable brand, chances are that you got two dead units.. its been known to happen. also make sure you got the opti spline drive lined up correctly.

[nickhinton]

Just went through my tests from the FSM, I have all specified values at the opti harness on the car side, nothing coming from the opti while cranking as far as voltage. I have 45 lbs of fuel pressure on prime at the rail. I can manually operate my injectors as well with a test light and they click and fuel pressure drops. Only thing left according to FSM and my thoughts has to be the OPTI. This controls fuel as well as spark right?

[firebird_1995]

The opti tells the pcm the location of the cam and crank which control fuel and spark delivery. You most likely have a doa opti.