Low Maf Reading Trouble! (S3-APY-210)

[ukku]

Hi, I recently owned an Audi S3. It's 2000, APY engine (with esp).
It seems a bit slow and maf readings are a bit low. (10-15 grams for the whole rpm range)
Depends on logs, there is no boost leak. Requested and actual boost seems closer.
On vagcom channel #32, trims are about %1-2.
I tried to find a vacuum leak with carb cleaner, but i couldn't. I think there is no leak.
It's not mapped and It's completely stock except for supersprint catback exhaust.
There is no fault on vagcom.
What should I do?
Can it be collapsing turbo inlet pipe?

Notes:
I have bought a brand new K04-022 with new exhaust manifold.
I have bought a brand new MAF. (And tried another MAF, nothing changed.)
I fitted a Leon Cupra R (BAM) fuel pump to try, but nothing changed again.

Log:

 

[jitvv]

Hi Mate,

Could be a number of things, check your DV and also do some logging on 002 031 115 and another run on 020 118 112 and post results up here i am sure someone could help. Not me though as i am still learning about VCDS. lol

 

[badger5]

new genuine maf?
check for leaks (smoke test will reveal some probably)

 

[ukku]

Hi Mate,

Could be a number of things, check your DV and also do some logging on 002 031 115 and another run on 020 118 112 and post results up here i am sure someone could help. Not me though as i am still learning about VCDS. lol

I checked my DV with this method: http://www.vaglinks.com/Docs/Misc/VAGLinks.com_DIY_Testing_a_Bosch_Diverter_Valve.pdf
And it seems ok. By the way, It's N revision, TT225 dv.
I had logged #020, there are so rare ******* from 0.3 to 2.8. Seems ok.

new genuine maf?
check for leaks (smoke test will reveal some probably)

Yes, it's genuine maf from VW/Audi.

 

[badger5]

smoke test is where I start pretty much always these days
pcv pipes rot out causing lost performance

 

[ukku]

smoke test is where I start pretty much always these days
pcv pipes rot out causing lost performance

I found a broken pipe (from pcv) and replaced.
I think there is no leak more.
But maf reading is still low.
Tried new coils, nothing changed.
Silicone tip fitted. When it reaches 5800-6000 rpms, ecu starts to ****** around 6-7s. And dont want to go after 6000.

No leak, new maf, engine load drops, boost drops, maf drops, ******* rises..
What can it be?

 

[karl210]

this might not be your problem but ive been struggling with powerloss for a while now and the other day i thought sod it i will do a pcv delete and it gave me 30g/s back!! I have an amk so it was easy i did it without a catch can and absoloutly no other parts except for jubilee clips, catch can and fancy blue piping arrived yesterday so hopefully i might get a little bit more because of a split in the y pipe still, definately worth considering

 

[<tuffty/>]

Undo the hose at the throttle body... if there is oil there try cleaning it then take the car for a quick drive and check again... if it does and you have done a pcv delete then chances are it's a tired turbo...

The oil in the inlet mixes with the air and fuel diluting the octane rating... this will promote engine knock and the timing pull you are seeing

<tuffty/>

 

[ukku]

Undo the hose at the throttle body... if there is oil there try cleaning it then take the car for a quick drive and check again... if it does and you have done a pcv delete then chances are it's a tired turbo...

The oil in the inlet mixes with the air and fuel diluting the octane rating... this will promote engine knock and the timing pull you are seeing

<tuffty/>

ok thanks. i will try this.
it's brand new turbo, so can't be.
i have bought a new 3way pcv hose, but problem goes on. Do i need a new checkvalve to restore pcv, if there is no leak?

 

[badger5]

if pcv is leaking/sticking you will suffer oil injestion = timing pull = bad for stock map

most common area for rotted pipes is around these

 

[ukku]

Hi again.
Today I removed n249, n112 and PCV.
Renewed all vacuum hoses with silicone.
Then had a leak test, found a clamp leak. I fixed it, there is no leak anymore.
But the car is still same.
Around 6000 rpms and later, it starts to ****** around 5-8 degrees. And maf reading drops from 5800 rpm 155 gr/s to 6800 rpm 130 gr/s.
So, performance is really bad especially on higher rpms.
Then disconnected the maf, tried again. Almost same. It ******* almost same. Performance feeling is almost same.
What can the problem be?
MAF?

 

[badger5]

oil in your pipes? check throttle body pipe for oil in there running out (high CF's is a clue)

 

[Rosso TT]

What about failing fuel pump?
Stick a fuel pressure gauge and see what the pressure does.

 

[brasiliangringo]

smoke test is where I start pretty much always these days
pcv pipes rot out causing lost performance

Which smoker tester do you use out of interest ?