I posted about random missfire last week and you wanted more info.I'll do my best to explain entire situation,but first the only mods i can comment are external.It has moroso air filter and intake tube,a BBK power plus throttle body,a borla exhaust or atleast muffler and the right side cat has been replaced but left looks original.The first thing i did when i got the car was install a new aftermarket opti because the previous owner had removed it thinking it had failed.The car started fine and i drove it a couple miles afterwards.The next night it would not start and it had a crank sensor code,so i replaced it.A few days later i tried to drive it and I let it idle for a few minutes and it sounded fine , then started down the road and the car started sputtering and kind of bucking and the tach was going crazy.Then the tach quit working and car smoothed and ran fine but had a code of P0372.While observing my scanner the only thing out of the ordinary was the missfires bouncing around the cyliders and thought it might be causing the poor running . It had some o2 issues and I think Igot those staight today .But after checking o2s I went to put some gas in it and alot of pressure came out when I removed gas cap .I fueled up and now I'm getting very long crank times and that p0372 code on every start ,but once started it sound fine and tach does not work . Not sure what you can do with this ,but its all of the issues.

 

Sounds like your "aftermarket Opti" didn't last very long. P0372 means you've lost the high resolution cam position signal from the Opti. Either the optical cam position signal is not leaving the optical module (faulty module), the harness connector is loose (does it still have the spring clip that secures it to the Opti?), the harness connector is corroded, or the harness pins are damaged.

What "brand" was the Opti? Is it an ebay cheapie?

 

Yes it was a e-bay cheapie,did come with a new harness though .The damn thing just quit on me and made me walk home a few minutes ago so i've learned my lesson on cheap parts,thank you

 

Yeah, it's worth it to spend the $400 or so on the opti! Quality matters with them-stupid things. If it's not name brand, I would get it.