RomRaider

Hi, i am currently tuning a M52b20 turbo engine and i am running into some maf issues
i thought i'd use the standard maf with a 2.2Kohm resistor and pazi's Excel sheet to calculate the new maf map. but the engine refuses to run correctly, AFR is Way to lean (in the 20's)

When running on the stock maf map evrything is fine with an afr of 12 on wot. untill the maf maxes out around 4500rpm

setup:
Stock engine
GT28r Turbo
350cc injectors(map rescaled and runs fine with stock maf)
Innovate Wideband Lambda

What could cause this lean afr ? even with much to high values in the injector map i still get a lean afr using the 2.2kohm resistor and the new calculated maf map

what does your maf voltage do compared too when you use the stock maf scaling?

Also, did you do a read back to see if your changes stuck?

The voltage isn't really measurable, the engine won't rev over 2000 rpm with the edited maf table and runs bad. it even backfires. i verified that the changes were applied in the ecu

But you should be able to log both Maf V and mass airflow. And if this
Is according to your maf scaling.

Btw, I Needed to retune when I switch maf+resistor too.
Maybe you just need a retune.

Not sure what you mean by it isn't 'measurable'.

Log the MAF Voltage... What does it say?...

Also, do you suspect your resistor install? It goes in series, not parallel to ground. I assume you know this but just posting for clarity.

Also, the excellent MAF spreadsheet that I've used is by Murray (ba114). Not sure if Pazi also has one, but I have not confirmed it.

The engine runs really bad, backfires, can't get up to speed/rpm. So i can't really log/measure the voltage. untop of that my laptop battery died yesterday so we could only test stationairy without load or boost.

I soldered the resistor in between the yellow signal wire, Not to ground.

What i did notice that the Stock maf with Stock maf map also did never reached full capacity, should be around 730Kghr, but never got over 500kghr with a max voltage of 4,7V

Could the maf sensor be bad and cause all of this with a resistor in place ?

Problem solved using another maf

Verstuurd vanaf mijn G8441 met Tapatalk

If you can connect to the ECU, you can REALLY measure the MAF voltage... Doesn't matter if the engine is running or not...

i mis understanded you, thought you meant measure/log to see what the maf did while driving the car.. but anyway its solved now by changing out the maf sensor. Car drives without any problems trough the whole rpm range, with an WOT afr around 12/13. and a cruise afr of 15

what setup are you using ?
stock CR ? you only mounted the turbo and 350c ?? and the maf mod ??
another thing just for my information i wanna ask you about the fuel consumption for like ?L/100km? ( just to have an d idea )

Since when B20 MAF is capable of 730kg/h? B28 MAF is linearized up to 725kg/h, while B20 one only up to 518kg/h...

Can you explain how you solve problem