is this MAF broke on an A4 tdi?

[matt-doyle]

got these results from logging block 3 on an A4 TDI which is really lacking power. Do they mean anything to you?

Engine speed MAF (specified) MAF (actual) EGR duty cycle
861-945 240-340 240-340 Apr-84
/min mg/R mg/R %
2352 625 360 19.9
2352 595 390 19.9
2352 595 370 19.9
2352 645 375 19.9
2352 690 405 19.9
2373 770 430 19.9
2373 850 445 4.8
2373 850 465 4.8
2394 850 480 4.8
2394 850 480 4.8
2415 850 490 4.8
2415 850 490 4.8
2415 850 490 4.8
2436 850 495 4.8
2436 850 495 4.8
2457 850 500 4.8
2457 850 505 4.8
2478 850 500 4.8
2478 850 505 4.8
2478 850 505 4.8
2499 850 505 4.8
2520 850 505 4.8
2520 850 510 4.8
2520 850 510 4.8
2541 850 510 4.8
2541 850 505 4.8
2562 850 510 4.8
2562 850 510 4.8
2583 850 510 4.8
2583 850 505 4.8
2604 850 510 4.8
2604 850 510 4.8
2604 850 505 4.8
2625 850 510 4.8
2625 850 510 4.8
2646 850 505 4.8
2646 850 505 4.8
2667 850 505 4.8
2667 850 505 4.8
2667 850 505 4.8
2688 850 500 4.8
2688 850 505 4.8
2688 850 500 4.8
2709 850 500 4.8
2709 850 500 4.8
2709 850 500 4.8
2730 850 500 4.8
2730 850 500 4.8
2730 850 495 4.8
2730 850 500 4.8
2730 850 495 4.8
2730 850 495 4.8
2730 850 495 4.8
2709 850 495 4.8
2709 850 495 4.8
2709 850 490 4.8
2688 850 490 4.8

 

[matt-doyle]

...answering my own question I know but it may be useful to someone in the future. Just read this on tdiclub.com faq...

MAF sensor - checking and replacement - With VAG-COM, confirm that in measuring blocks 3 with the engine at warm idle in neutral with all accessories off, the requested and actual airflow rates closely match each other (specifications: 230 to 370 mg/stroke) until the engine has been idling for a couple of minutes, after which the reported airflow should increase to approximately 480 (plus or minus about 30) mg/stroke. At 3000 rpm full load (test can only be done while driving) the reported air intake quantity should be at least 800 mg/stroke. If your sensor does not pass these tests and the intake system is known not to be excessively clogged, replace the MAF. The Pierburg MAF cannot be used as a replacement for a Bosch, but a Bosch MAF for a 2.0 gasoline engine vehicle will work fine in a TDI and may be a lot less expensive...

looks like the MAF is knackered.

 

[sssstew]

yep correct looks knackered.