[stlark]

hi, audi a6 2.5tdi v6. these are my first try with vagcom group tests. could someone have a look and tell me if anything is wrong.
maf test


group 011 test


thank you.

 

[ToeBall]

hi, audi a6 2.5tdi v6. these are my first try with vagcom group tests. could someone have a look and tell me if anything is wrong.
maf test
View attachment 639

group 011 test
View attachment 640

thank you.

It'd help if you log the pull in just one gear. What I do is have the laptop setup so I just have to tap the touch pad to start logging. Accelerate and set up for a 3rd gear pull. Hit log and then hit it through the one gear. Also, do a secondary scale for your N75 Duty Cycle so we can see what's going on. Personally, I use RPM as my scale along the bottom as well, but that's optional, especially since it's not linear.

Here's one of mine, so you can see what I'm talking about.

 

[chittychittybangbang]

Yes, your MAF sensor or circuit is dead. MAF actual is a flat line, it should roughly trace MAF requested. Either the sensor or the wiring is bad or you have a tuning box which is fooling the ECU.

 

[stlark]

hi, thank you both for your replies. i disconected the maf and the car would not respond at all, so the wiring could be ok? i will try and do a second group test in one gear and post the results.
i scanned the car and it came up with this fault code

1 Fault Found:
00553 - Mass Air Flow Sensor (G70)
27-00 - Implausible Signal

 

[chittychittybangbang]

That's because you disconnected the MAF. The sensor could be bad since I only see a flat line coming out of it. (maf actual) Something is strange with EGR duty cycle too, it should be going up and down.

 

[stlark]

thanks for reply. here's my 3rd gear test for maf and group 11


maf


group 11


would you recommend i change the maf or N75 ??
my actuator failed and i replaced it five months ago, i dont know if thats helped to make things worse. since then i have tried to adjust it but really dont know what to do.

 

[chittychittybangbang]

I would start with the MAF.

 

[stlark]

buying new maf today. fitting after work. will post results.

 

[stlark]

fitted new maf and these are the results. please advice. thanks.

maf


group 11

 

[chittychittybangbang]

Well gosh, that's even worse....some other possibilities: MAF plug or wiring issue, EGR problem, or exhaust clogging. Can you start with a reminder of everything you've checked or done to the car up till now?

 

[stlark]

thanks for your reply. six months ago car kept going in limp mode no power? changed two n75 units near diesel filter and also one near water tank in the engine, changed all pipes leading to n75's, only to find that it was the actuautor that had failed. replaced actuator. i had used six different garages as all were charging money to check on their computers but could not find the faults first time. audi would not entertain me because i had bought actuator from somewhere else. as they wanted me to buy whole turbo unit. a month ago i had whole timing belts and tensioners changed hoping that it would help. i have paid alot of money to mechanics with very little in return. thats when i decided to invest in vagcom and try and solve the problem myself. the actuater rod setting is the only thing that was not done by any mechanic. as all my problems started from the actuator failing in the first place.