Airflow/RPM Log: Analysis & Optimization

Hello!

I just took my AJM for a test drive because I noticed it felt a bit weak.
I noticed that at 3200+ RPM, the reported air mass value drops. Is this a sign that the mass airflow sensor needs to be replaced?


'010 '001
MAF: Mass Air Flow
Engine speed: Drehzahl
mg/H: milligrams per hour
rpm: revolutions per minute
mg/R /min
460.6 903
460.6 903
519.4 1386
539 1470
681.1 1554
597.8 2142
607.6 1302
837.9 1680
837.9 2121
739.9 2520
700.7 2919
524.3 3318
671.3 2604
980 2268
872.2 2478
891.8 2772
882 3045
842.8 3276
543.9 3360 <-
646.8 2478
627.2 2499
646.8 2541
641.9 2562
960.4 2604
877.1 2709
901.6 2835
891.8 2940
901.6 3066
891.8 3171
872.2 3276
563.5 3360 <-
504.7 3360
514.5 3234
524.3 3150
524.3 3045
553.7 2940
602.7 2877
602.7 2814
558.6 2751
529.2 2688
548.8 2625
563.5 2583
568.4 2520
568.4 2478
568.4 2436

Personally, I believe so. Inmo has VTG turbochargers with a healthy LMM (Lambda-Measuring-Module) that have a value of over 1000 mg/r. The limit, depending on the label file and engine, is around 1250 mg/r. According to VAG, anything below 850 mg/r is considered scrap.

'Interestingly, the value is around 3000 RPM.'

901.6 3066

This isn't too bad, but the radical drop-off is a bit too significant (see the value at 3300 RPM). The trick with the hole might help for a while. But eventually, this MAF sensor will fail.

Yes... I was almost certain. Again, either 85 euros or 49 euros on eBay. I still have a Pierburg lying around, but for some reason, it puts the engine into limp mode.
Consistently reports values of 1200+.

Constant values suggest a diode or similar component. However, this doesn't work with the AJM. We tested it for 4 hours with increasing enthusiasm. }

No, no. Not a diode. I bought that originally with the required approval documents (ABE) from the car parts center GAD. It also cost around 90 euros. Initially, the part worked quite well, but then it suddenly went into emergency mode after about 4 weeks. Measurements showed a lambda value of 1253 mg/m³.