jlt108

I am having problems with my 95 LT1. At first, every so often it would take longer to start but it would eventually start and run ok. Then while driving one evening it began to run extremely rough and shut off. The engine would turnover but would not restart. Also, there was some smoke and smell of fuel like it was flooded. The next morning it started but idles extremely rough and will shut off after about 10 seconds. If I press on the accelerator it will usually produce some smoke and attempt to backfire. I checked the fuel pressure and it holds firm at about 42 PSI. I have not checked the spark yet. Could these symptoms indicate an OptiSpark problem? Any ideas or help would be greatly appreciated?

H P Bushrod

How many miles are on your car? Judging from the symptoms you described, It sounds like your Opti-Spark has gone south.

MikeC4

with Bushrod, sounds like it is headed South and 'aint coming back, but how many miles on car? My secong "guess" would be your fuel pressure regulator.

Short pin 4 and pin 12 on your ALDL, and see what codes have been thrown from your PCM. Codes will flash where your LCD fuel gauge normally displays.

jlt108

approximately 110K

sothpaw2

If that's the original opti, just replace it anyway. 100k for the opti is super great life! There are guys here who don't drive their cars much (3-5k per year) that replace optis every 20 k mi!!

I did mine at 75k but not due to failure, due to convenience (engine was apart).

MikeC4

If you do end up replacing your OptiSpark, also replace your waterpump. A leaking water pump can kill an Opti. If you can, check the weep hole at the bottom of your WP for leaks....

Lastly, some on this forum recommend the Dynotech GenII Opti instead of AC Delco. They improve on some of the inherent weeknesses of the AC Delco, but it is considerably more expensive:

http://www.dynotech-eng.com/dynaspark.htm