Well hello there. I have been lurking around these forums for quiet a while now and it has been much help (thanks to all the great posts) but now im stuck

The project: Supercharged 540i (4.4liter v8 variable valve timing) with 39lb injects (original 19lb). The DME is a ME7.2 which is REALLY similar to the ME7.1 that you guys are working with.
The maf we are using is original BMW one.
A?F ratio im talking about are measured with a stand alone wide band sensor

Before any tuning, the car would start up and die if i dont give it gas. When i did give it gas, it would run at 10:1 or even richer!

At this point, we have scaled down the KRKTE to 0.1300 (from 0.1700) and now the car idles great at 14.6 to 14.8.
We also lowered WOT and Partial throttle timing few degrees just in case for now until i get the car running well and get my ass on a dyno

Now the problems starting to happen when i go on a test drive. Slow cruising (while the SC is in vacuum and bypass valve is open) is NOT to bad and my AF ratio about 12 or 13. I know that is pig rich but that is not too bad for now.

Once i get on the boost, thats where the problems start happening.  Here is what happens:
Im at 1600rpm in second gear and I floor the pedal to WOT.
Fuel ratio goes down to 10.0:1 or even lower.
Boost kicks in and car pulls strong between 1800rpm and 2000 or so.
Then the car looses 80% of its power for about 1 or 2 seconds or 500rpm.
The AF stays at 10:1 or so.
after about 2500 rpm, the car just shoots out like a rocket and pulls strong till 4000rpm with AF at 14 or 13:1 (way to lean!)
After 4000 rpm it looses all its power once again
1 or 2 seconds (about 4400rpm or so) later, it shoots out like a rocket once again and pulls all the way to redline with air fuel ratios of 14 to 15:1 (way to lean again)
--All of this is at WOT and in a single gear


I know im doing MAJOR modifications to my engine by going from NA to FI and i know i need way more tuning, but im kinda stuck now. So far, the only functions modified are: idle rpm, KRKTE, and P/T and WOT ignition angles



From my research, I see that our computers calculate fuel injections based on load. So i guess i woulod have to be playing with load now.

I would appreciate if anyone can point me to a right direction!

THANKS so much guys!

The injector calibration is the first thing you need to get right.  I would have done this without the super charger.  Can you bypass the charger for now?  Doing this you need to get the car driving with the new injectors as it did standard.  You need to adjust injector latency TVUB as well as KRKTE.  You do this by monitoring your fuel trims.  Next, the MAF limit will need raising as you are likely to exceed it pretty quickly with the charger.

Rick

What kind of sensor element? not all mafs are reverse flow sensing, depends on type of maf calibration and sensor that is used.

I don't know where you're getting your MLHFM from, I just had a quick look into an E39 540i ME7.2 file and it looks like MLHFM is 100% normal, not weird like you're showing us. I think sometimes people just getting random damoses and taking them for gospel is just as bad as not having anything and trusting an idiot tuner.

Im finally getting somewhere. Idle is good steady and cruise is good BUT high load at partial throttle (more then 46% load in 6th gear on freeway), the car leans out completely. At WOT, im getting about 11:1 until about 5K rpm and then it leans out again.....so more tuning needed

Now, question for the experts: Do i have to tune KFMIRL and KFMIOP now that the engine is boosted? If so any tips on that?

Also, im planning on tuning for mafless setup. Ill be running MAF all the time but if it fails, i want to have the backup security of mafless Alpha N tune. Now any idleas how i can do that?
SO far, without maf the car idles and cruises ok but at WOT, it LEANS out completely.

Thanks 

Really hate to bring this thread out from the dead


were you by chance working with the E5A0_000.a2l or were you working with a DAMOS file?