idle issues

[nip]

its me mad, right here goes, the setup is 3076 turbo standard injectors, maf ,n75,ecu has a super chips chip in it.
The set up also has bigger I/c, ported/polished head due to waiting to have it remaped im driving it around with no boost , problem is when the cars hot slowing down to a stop it cuts out or the revs drop to about 3-400rpm then when at standstill the idle starts to wonder, if I then rev it it puffs out a bit off black smoke.
things ive done
cleaned/changed isv
cleaned maf
changed vac pipes
vag commed with engine speed sensor fault
changed n-75
and coil packs

ive been told that due to bigger cooler/turbo its the map on the ecu hope someone can shed some light on it as its really driving me mad, have nearly come to to decision to break it
regards nip

[nip]

Anyone?

[DJones]

Your first post looks to have covered the most obvious points making it tough to give advice without seeing it, it's definitely nothing to do with having a bigger inter cooler or turbo, these parts will make no difference to tick over.

I think I would start checking the wiring to some of the components you have checked.

Does the throttle body's micro switch click when you slightly open and close the throttle?

[nip]

Cheers daz, I've checked the switch it does click , I've also unplugged the isv, tps whilst running and it clicks the n75 , the only other thing I have noticed is if I rev the engine to say above 3 thou the n75 starts to click

[DJones]

If its puffing out black smoke then it's over fuelling but without seeing it its guess work as to why..

The only time mine was stalling on over run was when the ECU could not see a road speed signal and I had the lights on high electrical load etc.

The lamba would be the next area I would check.

[twoqu]

If you have Vagcom then you might as well use it to try and troubleshoot your issue.
Go here and downloaded the ABY Motronic manual:

http://www.s2-audi.co.uk/work_shop.htm

Compare the readings of the measuring blocks against yours to see if it gives you a clue. You can also test the TPS to see if the ecu is seing its open or closed or use the output test to see it working. All the procedures are explained.

[nip]

If its puffing out black smoke then it's over fuelling but without seeing it its guess work as to why..

The only time mine was stalling on over run was when the ECU could not see a road speed signal and I had the lights on high electrical load etc.

The lamba would be the next area I would check.

I forgot to add I changed lamba too , funny you saying that about ur light being on I ways have my lights on and when I turn left or right it dips the revs at idle

[nip]

If you have Vagcom then you might as well use it to try and troubleshoot your issue.
Go here and downloaded the ABY Motronic manual:

http://www.s2-audi.co.uk/work_shop.htm

Compare the readings of the measuring blocks against yours to see if it gives you a clue. You can also test the TPS to see if the ecu is seing its open or closed or use the output test to see it working. All the procedures are explained.

Cheers twogu, Il try that

[Greg_S]

Also take you ISV off the and check the valve is actuating properly. I had these problems previously and changed the TPS because the switch for closed was no longer working. Then I found out the idle valve (ISV) was sticking.

If you make a quick MIL tester you can run the output tests without the need for a VAGCOM aswell.

Details on that are here: http://www.s2forum.com/forum/showthr...&postcount=192

[nip]

Also take you ISV off the and check the valve is actuating properly. I had these problems previously and changed the TPS because the switch for closed was no longer working. Then I found out the idle valve (ISV) was sticking.

If you make a quick MIL tester you can run the output tests without the need for a VAGCOM aswell.

Details on that are here: http://www.s2forum.com/forum/showthr...&postcount=192

I've changed the isv I've cleaned both out, what's a MIL tester?.
I can try later cheers Greg

[europeanme]

is the turbo a 360° bb?....

this is exactly what mine was and is doing...not so much the black smoke but the cutting out at virtually every light/junction etc...

[nip]

is the turbo a 360° bb?....

this is exactly what mine was and is doing...not so much the black smoke but the cutting out at virtually every light/junction etc...

Yep mike it is, I find that driving it off boost it don't want to cut out that much

[europeanme]

is yours mapped/set up for your turbo?...

[nip]

is yours mapped/set up for your turbo?...

No mike not yet, I'm waiting to have it mapped

[twoqu]

Strange you should mention that its a Garrett. Seem to recall back in the midst of time that these kinds of issues were common and led to the pressure side Maf installations. Why that should be the case I am uncertain but it sort of implies an issue with the Maf somehow.
Of course this issue does not seem to occur on all Maf equipped Garrets. If it is somehow a Maf issue and you are still on Motronic and need it mapped then I beleive PRJ could do a mafless tune.
Not quite sure what map you are running but if it is a Superchip then they did something funky with the map (bodged) although you would have thought that the idle part is one which would not need any tweaking. Who knows!