Whiteaw57

iTrader: (2)

Hey Guys,
I have a cammed 98 z28, What I'm curious about is the open loop tune. I bought the car the way it is and since its gotten colder it's very obvious that the car was tuned in the summertime. It seems like the magic number is around 35*. If it gets around that cold overnight when I crank it it usually will stumble and fall on its face. When I try to crank it back up it hesitates to start(have to turn it over about ten times) then will cut up and chug terribly around 3 or 4 hundred rpm. I give it a little gas to keep it running and keep oil psi up and it runs with an obvious miss for about 5 or ten seconds then clears up and goes into its normal sounding warm up.

My question is: Is this going to hurt anything? I dont know enough about fuel injection to be the judge. The other question is, Is giving it throttle to keep it running like this harmful? Lastly If it is Bad for the motor is there a good way to tune for it or do I have to take it to a tuner and hope it gets cold enough for him to play with it when it acts up

TIA

racecar

Do what you can to get it started, a good tune would be better. Adding fuel to the OLFA (open loop fuel air) table will make it cold start better That will also change WOT fuel...

macca_779

The best advice I can give is don't screw with the base tables. If it works in summer then they will work in winter. So alternatively, only play with ECT/IAT factors around the temps your now experiencing.

edcmat-l1

iTrader: (10)

Yep. OLFA from the problem temp down. That and base idle airflow from 32 deg down, add some, then run the histogram.

Whiteaw57

iTrader: (2)

Haha you guys are speaking a foreign language to me. I had it do it to me last night as well. It's not impossible to start, it just scares me how it acts. I think if It will survive Ill just wait and get it through the winter. The main thing is that I don't hurt the engine somehow doing this. Thanks for all the replies