I installed a MSD opti two months ago and have had hard starting . Now the thing wont start at all. When the starter is keyed off the engine will turn backwards a few times. Any ideas would be appreciated.

 

Have you scanned it for codes? Have you checked the two ends of the Opti harness for corrosion or damaged pins? When you installed the MSD, did you loc-tite the rotor screws?

I'm going to assume from your screen name that you have a 95, hence a vented Opti driven by the cam dowel pin. Since it ran sort of fine for a while, we'll assume you have the pin in the right hole in the back of the Opti.

Might want to add a "signature", with basic info about your car - year, model, engine, tranny and any major mods.

 

I dont remember lock titen the rotor screws. The harness was a new part with the opti. The weird part is that the fuel is there , the spark is there but the engine just wont fire . I have even tried a shot of ether and that didnt even get a chug out of it. The coil is a new msd . The spark plugs are new ngk. The wires are new msd. I had a bud scan the car when i first installed the new parts and there were no codes.

 

But it ran better when you first installed the parts - might explain why there were no codes then. Now it won't start at all. Might be time for another scan. Just to clarify, when you installed the MSD Opti, the only problem was hard starting. Other than that, can we assume it ran fine - idle, low RPM, WOT, max RPM?

Only unchanged part of the ignition system appears to be the IC Module.

With the MSD, if you don't loc-tite the rotor screws, there's a good chance they will fall out in short order.

How did you verify fuel? How did you verify spark?

 

I have replaced the ignition module and have changed to a lt4 knock module. I did a fuel pump test useing a gauge at the test port on the f rail. The fuel pressure reg. also appears to be ok. I used a test light on the injectors. I used a timing light on no.1 wire when cranking the engine and it would light up at about tdc.Im wondering if it may have jumped a touth on the timing chain. 1995 z28 SLP cold air throttle body bypass flowmaster catback Moser 12 bolt 3.73 umi and sponn rear suspension T56 6sp short stick hypertech download w/160 stat

 

I have found the problem is a weak coil.When the opti finally got bad enough that the car was hard to drive the security light came on and also became very hard to start. I had replaced the stock coil with a msd last july when the engine developed a miss at high rpms . I dont know how but the opti going bad and the misfire that it caused fried my vatts and damaged the coil. I bypassed the vats and called msd and decribed the trouble that i was having. I was told to return the opti for repair or to be checked over. I decided to try the old coil before going to the work of removing the opti.The engine fired the second i hit the key.That was 3 wks ago and the car is running flawlessly. One more thing, The new plugs that i installed last july at the same time as the coil were damaged and i replaced them with ngks.Msd is going to replace the bad coil too by the way.