NefMoto

Installed Rs4 maf  and copied mlhfm for rs4 bin. Checked my file this a mbox still can't figure out was is the cause, other than mlhfm is there and other maps that needs editing.

That log is useless. You are already in limp.

Get a log before it goes limp

Here is a log with no limp mode, didn't go wot till after 3k rpm may need to work on kfkhfm or ldrxn engine load is way above request

You need to somehow log a run that *causes* limp mode... not before limp, not after limp..

That one didn't actually cause limp (or shouldn't have, anyway) as far as I can tell.

Load reading high is usually the result of an overscaled MAF. An overscaled MAF is the number one cause of positive deviation in a leak free system.

Earlier you said log was no good due to limp. Only way to no go in limp is if I get the car wot at about 3k rpm

I installed the rs4 maf and copied mlhfm from a f box bin also set mlofs to 200.Did I need to use mlhfm from a different bin

You sure it's an RS4 housing AND sensor?

yes ordered it from ecs tuning

Is it aftermarket, or OEM? If it's aftermarket, throw it in the trash. Get a used B6/B7 S4 MAF and call it a day.

Its a bosch oem

ECS is full of Chinese OEM crap.  Watch out what buy from ECS !   Don't get me wrong , ECS has good stuff too but they are selling more and more Bosch replica crap and other stuff


LEE

You need to log it AS it goes limp, not before, not after..

The sensor housing has part#0280218067 and the box the sensor came in has part#077133471k. Did a search for the part #471k came back as maf sensor for b6/b7 s4, so I guess I need find b6 s4 bin & xdf

B6 S4 MLHFM is the same as B5 RS4.

If I use the maf I had on the car before I don't get deviation, but with the rs4 maf with kfkhfm set to all 1s there is deviation. the only time I don't get deviation with the rs4 maf is if I set kfkhfm to .93

Something is off there, bc oem RS4 KFKHFM is 1.024 across the whole board.
I agree with DD, are you sure it is RS4 oem MAF and sensor?
BC, i bought one myself, and i got the same problem. act load way above req.
Bought oem Maf and evrything was OK.

How is fueling when you overshooting that muck load? Way too rich?

Oem based on info on box and sensor itself. if I wait till around 3k to go wot so I don't limp, load around 260 with request 230 and afr 10.8

THE.
MAF.
IS.
SHIT.

Please post logs showing large positive deviation (which is UNDER boost, btw) BEFORE the car goes limp. If you are seeing 10% WGDC, it is already limp and the log won't tell you jack.

I'm guessing boost leak or DV failure.

Or possibly insufficient I-Max at redline (on the one good log, I see there is some deviation at redline, and pre-lin meets the ilimit)

I don't see how this has anything to do with a bad MAF btw.

And you are targeting AFR 12.5???

Yes target afr is about 12.5. I increased kfldimx, did a few wot run and car didn't go into limp or give deviation code. The load is still a little above request with kfkhfm set to 1s

Have you checked your imax trims? (ldimxa_#)

If they are positive, I'd imax up a bit, clear codes and relog.

The ECU could be trimming your imax upwards for you.

I still think his MAF is reading high.

 ??? Boost leak  ???. Are you sure the ''Y"" pipe is in good order  ??? put you hands on the ''Y'' pipe at the throttle body and check if it is ripped on the bottom  ::)

Lee

It is, SLIGHTLY, but that doesn't explain boost deviation

It absolutely does. MAF reading high will trigger premature leak diagnosis.

I think the problem is with this maf from ECS, in the pic below actual boost is 25 psi at 3750 rpm and at same point load is 254. also think I need to adjust kfldhbn once I get maf/limp mode fixed

hmm, and I bet your maf readings are way high for the power it outputs??

MAF readings are high for the amount of air actually flowing into the motor :P

ps_w vs MAP is a good indication of whether your MAF is correct or not, since fuel trims can be compensated by KRKTE/TVUB adjustments.

Here is a log before the car goes limp

Are you sure you don't have a boost leak ??  Hint hint ....

Lee

Too much load request too soon. See tuning page on s4 wiki on positive deviation

I think i figured out what is causing the positive deviation. My clutch is slipping causing actual load to increase too quick, I looked at few log which showed really high torque.I have a b5 rs4 clutch kit,I guess it time now to decide what stage 3 clutch kit to get