JonB

iTrader: (3)

Today i went out and changed my slp maf back to my stock. I have headers going on soon and i understand that tuneing with an aftermarket maf is a pain so i just took it off now. Well I went for alittle drive and had some detonation problems at wot. When i first took off in 1st it blew out some black smoke and then at about 500rpm before the rev limiter the pig started pinging like crazy. I then did abit of varying of rpms in different gears but noting wot till alittle later. Then i gave it another shot and the same happened only I did't see the black smoke out the back. I run nothing but 93 octane. Is it just the computer relearning from the switch? I never remeber it doing before with the stock maf or the slp for that matter. I do have a predator and have the performace tune installed and if it does't stop I was thinking of adding some more fuel. Anyone know how much I should add?

Thanks
Jon

jimmyblue

iTrader: (11)

Use the Predator to look at the WOT O2 readings. On a stock
exhaust car shoot for about 900mV. If it goes below this at
the point of ping, but is otherwise healthy at lower RPM, look
for fuel delivery troubles. If you have 900-ish O2 voltages on
both banks, take out a little spark and see how that does.

It may take some time for the PCM to learn back, but a lean
problem at WOT is not likely to learn in your favor I expect.

JonB

iTrader: (3)

Ok thanks. I'm gonna run it around some more and see if it just needs to relearn if its still there after a couple days i'll start fouling around with the predator and see what I can do.