Phil99vette

iTrader: (11)

I am working on a 00 C5 with a pretty stout engine combo and for some reason the engine is not responding to VE changes. I've checked the file 3 times and everything looks perfect, MAF Fail is @ 0, Closed Loop Temp is 284, I've got the correct commanded A/F ratio. I just can't seem to put my finger on why the car is not responding to the changes made to the primary and secondary table. Another thing is the CE light is not coming on to show MAF fail. Could a low voltage battery cause this?
Phil

jimmyblue

iTrader: (11)

What do you mean by nonresponsive? Wideband idle
readings, or what? What change are you looking for,
and how?

Look at the DTC section of the tune and be sure the
MAF fail codes are not turned off.

white2001s10

iTrader: (4)

do you have your MAF unplugged?

Phil99vette

iTrader: (11)

I have speed density tuned many many cars and this is the first one to do this.... I've done everything in the ECU to set it up for SD mode and when I try to add fuel it just doesn't add fuel. I've added 2 rounds of 20% of fuel and no luck.
Phil

DramaFoYoMama

It sounds to me like the MAF isn't failing out for some reason. I tuned a car once that would never go into SD unless you unplugged the MAF, even though it was set to fail. I know on Vettes that you can't just unplug them because the IAT is in there as well. Has it even set the DTC yet? I bet it isn't in SD.

BLK02WS6

iTrader: (2)

Try setting all of the values in the MAF table to "0" and see if that works. That is what I do while tuning the VE in speed density.

Dixit

iTrader: (1)

I thought an 00 vette you can unplug the MAF since the intake sensor is actually on the air bridge. I know on my 2002 the intake sensor is built into the MAF sensor as well. I know the 99 definetely had it separate from the MAF, but not sure on 00.

Dixit

Phil99vette

iTrader: (11)

Man, this thing has got me going crazy. Last night the car runs lean and needs more fuel. Today the car runs rich and needs less fuel. Its a big swing from last night to today. It feels like its finally in SD mode now.
Phil

MeentSS02

iTrader: (11)

I've seen this happen on mine when I first did SD tuning...zeroing out the MAF table was the answer for me. If the table holds no value, the PCM certainly can't use it, forcing it to go to SD mode a little quicker (at least that's how I think it works )