No matter what I change in the fuel table (mainly PE vs RPM) my AF always reads 9.6 on WOT... i've made'm go from +20 to -20 and it has not made a single diffrence... I've also made my BLMs = 128 @ WOT but that still didnt do anything...

then I went over to MAF calibrate and changed the values in there... but thats not the right way to tune I believe since I'm not going WOT even if the MAF frequency reads high... (also after that maf tune, i cracked a piston, dunno if it was relevant, but =/)

anyways... why can this be happening? btw car is a turbo lt1 (obdII)

my AFR only changes if i change the MAF values...

 

Where are you getting the AF ratio numbers from?

Rich

 

a wideband

 

Maybe when you run at WOT you're still in Open Loop? If thats the case, no matter what you do to your PE table, your AFR will stay the same as it doesn't not effect Open Loop operations, trust me I found out after scratching my head about that one LOL.

 

I am sceptical of the accuracy of 9.6:1. Does it black smoke like crazy? It would at 9.6:1. In fact, many motors would stall. Most shut off at ~10:1, in my experience. At least it ought to stumble and generally run poorly if it were that rich. IOW, I am trying to verify if it's really that rich. Are the MAF readings maxing out at very low rpm due to the turbo?

Rich

 

Do you have an FMU that's boost referenced?

As you probably know, with many FMU's, as the boost increases, so does the fuel pressure causing more fuel flow.

If you have one, I guess that could be part of it too.

Is your tune adjusted for the size injectors you have?

 

its 9.6.... the dyno wideband shows it, and so does my wideband tool....

 

More info would certainly help. Details of the setup, info from the PCM datastream, fuel pressure, etc. I still don't have an answer to my question: is it black smoking and running like a turd when it shows 9.6:1?

Rich

 

yes, def alot of black smoke... so much that the back of my car had carbon deposits on it (like it was all black)

No clue what PCM datastream is (like o2 info and such?)

its a turbo setup on a OBDII LT1, fuel pressure is 45ish, and 42 lb injectors (they've been tuned properly)

 

Are those FP readings under boost or at idle?

Rich

 

I could just be shooting in the dark but you mention that your using obd2 and that you have your LT set at 128. That would make your car run rich. Then again I could of missed something here.

 

FP readings?

i'm running 9.6 at WOT...

jdizzell, whats LT? did u mean BLMs? if so, u want ur BLMs at 128@WOT for a good tune i heard...

 

I hate to say this, but it almost sounds like you're in over your head trying to tune this car.
Maybe you need to enlist someone with some experience to do it before you crack more pistons?

 

Are you using obd1 or obd2? Long term(lt) is obd2 and block learn multiplier(blm) is obd1.

128 blm is 14.7:1 afr, 0 lt is 14.7:1 afr, if you are under 128 blm or under 0 lt, then you are running rich and the pcm will try to lean it out by shorting injector pulse width.

 

Actually you make 14.7:1 at every BLM value (within range), not just 128. It's an adjustment factor to make 14.7:1.