Boost Issues

[Le S2 Audi]

I know this has been covered 1000's of times but can someone offer some advise please...

Just put the S2 back on the road....

I recently fitted an RS2 Airbox & MAF - which seems to be fitted properly..

Car had run out of fuel (Just) filled her up and went for a run and she was missing like mad... so pulled up and checked her over and saw that the MAF Wire & plug wasn't connected properly - fitted it and then she ran much better...

Until you open her up fully and she hits 1.4 bar for about 1 second and then tails off to 0.5...

She also has Homefries... Could she be in safety mode??

Don't think its a boost leak as it happens no matter where the revs are just hits full boost and then goes to limp mode...

Any suggestions??

Thanks guys!!

[prj]

Was MAF new?
Does it go to 0.5 bar and then stay there until you restart the car?
Or if you go back up on the throttle it goes to 1.4 again?

[S2central.net]

It likely stored a code when MAF unplugged... remove ECU fuses for 30s to reset it and try again.

Air leaks, MAF plugs and other electrical gremlins can be the bane of these cars.

[Le S2 Audi]

if you hit the throttle sh will boost again for another second and then retard back to 0.5 bar...

When you throttle off completely she dips into the minus on the gauge...

[Le S2 Audi]

It likely stored a code when MAF unplugged... remove ECU fuses for 30s to reset it and try again.

Air leaks, MAF plugs and other electrical gremlins can be the bane of these cars.

I did try that - but not for 30 seconds.. Will try it again....

Would this show up on VagCom if I was to plug it in??

[S2central.net]

The 30s isnt a specific thing - just to stop folk popping them in/out too fast. There is large holding cap inside ECU... anyway - yeagh what does VAGCOM say ?

[Le S2 Audi]

The 30s isnt a specific thing - just to stop folk popping them in/out too fast. There is large holding cap inside ECU... anyway - yeagh what does VAGCOM say ?

Pulled the fuses & did Vagcom & got the normal 00513 Code Nothing else..

Gone for another run and same issue.. Hits 1.4/1.5 and limps back to 0.4 - if you try and hit the power straight after this it just wont boost... If you drop off the accelerator and let it drop into the minus and then hit the gas - she boosts again for 1 sec and drops back..

any other suggestions? sprayed the MAF with WD40 to see if that helps...

Could the MAF be faulty? Would Vagcom not show this issue?

[prj]

Could the MAF be faulty? Would Vagcom not show this issue?

Was MAF new?

Yes there is a way to diagnose bad MAF's.
But... is it new?

[Le S2 Audi]

No a used one...

[S2central.net]

Use VAGCOM to take look at Group 0 while idling... that might show up bad MAF... not always though - better to do a pull in 3rd or 4th if it lets you !

Report the 10 numbers from left to right in Group 0 - measuring blocks !

[Le S2 Audi]

Use VAGCOM to take look at Group 0 while idling... that might show up bad MAF... not always though - better to do a pull in 3rd or 4th if it lets you !

Report the 10 numbers from left to right in Group 0 - measuring blocks !

Sorry for being thick but how do I get - Group 0 - to show on Vagcom?? is that under engine settings??

[S2central.net]

with engine running enter the engine section...
then see a button called measuring blocks...
select group 0 from the menu on left

http://www.s2central.net/vagcom_4.html will help

[Le S2 Audi]

with engine running enter the engine section...
then see a button called measuring blocks...
select group 0 from the menu on left

http://www.s2central.net/vagcom_4.html will help

Thanks Paul - Mine's a small hand held unit but got this off the reader...
209 - 24 to 26 - 75 to 83 - 130 - 125
131 - 48 - 129 to 132 - 128 -36 to 37

But TBH it's just numbers and I dont have a clue what they mean sorry

[S2central.net]

MAF is marginally outside spec (20-24) for warm idle... hard to condemn it from here but I would borrow a spare if you can.
All other numbers are in range.

[Le S2 Audi]

MAF is marginally outside spec (20-24) for warm idle... hard to condemn it from here but I would borrow a spare if you can.
All other numbers are in range.

I have my old std S2 one - might stick that back on and see what happens...

Thanks Paul