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Discussion Starter #1
Hi Guys and Girls,

I have found this forum very helpful and if it wasnt for all the help and info from this site i would have given up on my van.
I have to say a big thanks to Festa T: will have to catch up at some point.:D

Would any of you technical kind T5 professionals tell me, if i am correct that my MAF is shot, i think it is?

Also i think i have found a faulty Lamda Sensor, but would this be because i have a DPF, and EGR Delete?

 

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2004 T5 2.5 174
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Well I can only tell you what I know. I don't think the Readiness means much except in the US where cars have to pass that test as part of their version of an MOT. The items in read are probably as the result of your EGR and DPF deletes.

As far as I know the best way to test the MAF with VCDS is to log a single group probably (group 3 in our case) which shows the expected/requested airflow and the actual airflow plus the load (throttle opening as in your log). You need to have the engine fully warm. Find a nice big quite hill where you can use wide open throttle in each gear. Once you have the log, copy and paste the main third and fourth gear parts of it (where full boost and mx air is being achieved) into a graphing ap/program. It makes it easier to see if the expected and actual airflows roughly follow each other. It won't be exact but it should be somewhere near.

I don't know if this is my T4 or T5 but whatever it is it's clearly not hitting the numbers.



You have two groups logged together there (often handy) but group 8 is just showing how much the ECU's smoke map is limiting power which isn't really relevant for this test.

Don't forget that the MAF only measures the air going past so if less air really is going past from say a restricted exhaust or intake, it will show as low even if the MAF is perfect.
 

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2004 T5 2.5 174
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I forgot to say if you get someone else to drive you can watch a ready made live scrolling graph of log by clicking Vag-Graph I think it's called.

You can forget all the grapghing stuff and just compare the raw numbers on the log of course but looking at that many numbers always seems a bit big eye boggling to me!
 
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