lathens

Hi All,

I replaced my optispark last weekend. While researching my optispark purchase on the internet and by reading reviews on Summitt, I found there were many cases where people have received a bad optispark straight from the factory. I also found a post where someone said it was a good idea to start your car after the opti is installed but before installing everything else to confirm the new opti is functional. So, I did this. MAJOR MISTAKE. What I didn't think through is that the mass airflow was unplugged. Computer has been dumping fuel and making the car run rich and load up all week. Car runs much better today, but I think I have multiple fouled plugs. Would running the car for a minute or so with the MAF unplugged cause this? Should I keep digging for other problems?

See this post also:
https://www.camaroz28.com/forums/lt1...-speed-884630/

Thanks,

Loren

Injuneer

When the MAF is unplugged, the PCM defaults to speed-density, using data from the MAP sensor and the IAT sensor. I suspect you may have had the IAT sensor unplugged as well, throwing the calculations off.

Additionally, unless your tuner updated the volumetric efficiency (VE) tables when he did the tune for the heads and cam, speed-density is handicapped with bad data.

lathens

Hi Fred,

Yes, MAP and IAT were unplugged also. So, am I right in assuming this is my problem or should I keep looking for other potential issues?

Thanks,

Loren

Injuneer

With MAP, MAF, IAT and the coolant temp sensors disconnected, the PCM was pretty much forced into limp mode.... it was missing all the critical data it needed to run the engine efficiently. Surprised it ran as well as it did.