Do you want an inexpensive increase in I5 20Vt power and refinement ?

[Vorsprung durch Technik]

I am sure it is, I am just giving a gentle reminder that no matter what you do, your engine is still bound by the laws of physics


Do NOT fit that to your car.

This is all very interesting especially that last comment.Whats wrong with it Dimitri? Why is it a bad idea?

[prj]

Afternoon Dimitri, good to see you're still lurking.

I wouldn't disagree with your comments, but it is definitely way better after the fitting of the three new items - coil packs, bypass valve, and WGFV.

I am sure it is, I am just giving a gentle reminder that no matter what you do, your engine is still bound by the laws of physics

http://www.s2forum.com/forum/showthread.php?t=42397

Do NOT fit that to your car.

[macspring]

Afternoon Dimitri, good to see you're still lurking.

I wouldn't disagree with your comments, but it is definitely way better after the fitting of the three new items - coil packs, bypass valve, and WGFV.

Even if it didn't need all three, if certainly benefitted from the coil packs and the WGFV.

To be honest right now, I 'm not gonna bother to swop back in the old Bypass Valve just to confirm that the performance remains as is, as I figure it can't be better than a brand new one.

I appear to unintentionally given the wrong impression with the earlier boost comment.

What I meant was that the car feels like it has more torque and feel less lethargic below 3k rpm. Certainly not saying it gives full boost at 2k rpm, it doesn't.

Thanks for you comments, very much appreciate your 'always informative' input on here.

Additionally, I'm sure I'm not the only one who enjoys your succinct posts.

Kind regards.

[macspring]

All good news.

I have to suspect that your WGFV was the main issue and not so much the BPV.

I need to correct you on one thing (Sorry, ) What you are referring to as the "Michelin Man" hose is not what everyone else calls that one. I believe you are talking about the MAF to turbo hose, which, for the AAN, people call the "MAF to turbo hose" .

The "Michelin Man" hose is the one between the cross-over pipe and the side mount intercooler (item 14 in the lower right corner of this boost leak test diagram):

Dave, apologies you are correct, on the UrS6 it is the one going from the crossover pipe to the intercooler.

Thanks for keeping me honest.

[Henkjan]

http://www.s2forum.com/forum/showthread.php?t=42397

[prj]

Sorry but none of these cars have full boost at 2k, not even in 6th gear.
2.8-3.2k is about right in 3rd gear depending on the state of tune it's in.

This is even with mechanical boost control. Old valve was just probably screwed, nothing else to it.

[geneandbolly]

I need to correct you on one thing (Sorry, ) What you are referring to as the "Michelin Man" hose is not what everyone else calls that one. I believe you are talking about the MAF to turbo hose, which, for the AAN, people call the "MAF to turbo hose" .

The "Michelin Man" hose is the one between the cross-over pipe and the side mount intercooler (item 14 in the lower right corner of this boost leak test diagram):

right prof - a query from the back row here: did audi call it "the michelin man" hose when they set up the spares list for the AAN engine?? i bet they really called the MAF hose after our rotund rubber -bodied buddy - if you look at the two it makes more sense as the MAF hose has little protruberences just like arms and legs . . (a bit like this explanation)

[hunker7]

Interesting, might need to consider changing WGFV as mine seems to take ages to boost, as you said, around 3k is when you feel it shifting.

[UrS4boy]

All good news.

I have to suspect that your WGFV was the main issue and not so much the BPV.

I need to correct you on one thing (Sorry, ) What you are referring to as the "Michelin Man" hose is not what everyone else calls that one. I believe you are talking about the MAF to turbo hose, which, for the AAN, people call the "MAF to turbo hose" .

The "Michelin Man" hose is the one between the cross-over pipe and the side mount intercooler (item 14 in the lower right corner of this boost leak test diagram):

[geneandbolly]

that's a similar experience as with the OEM "H" boost control valve. the one i bought from ebay looked nice and shiny (although second hand) so i took the replacement "J" valve out and fitted the "H" as should be fitted to the AAN engine.

RUBBISH!!

it had to have been a faulty valve as it felt like the turbo wasn't cutting in at all. i removed it, requested a refund from mr ebay seller and re-installed my "J" valve.

the result: car shall be re-named Le TGV !!!!



i must investigate that bosch gizmo you mentioned too . .

[macspring]

If so, please read this post.

1997 UrS6 saloon, bought last year with 40k on it, with the last 10k of those miles done in the previous 15 months by the previous owner.

So a fresh car with not too many heat cycles, but still 18 years old.

Ran well and pulled well for standard.

Replaced filter with a new paper filter. No change. But I was happier.

Took off and cleaned the throttle body with solvent. Was dirty. No noticeable change. But I was happier.

Fried it, but while better, a bit of a disappointment and not as good as I expected it to be. Have other I5 cars so knew roughly what to expect. Also seemed to only boost fully / properly at 3k rpm. Everything I’d read about the 20Vt engine always mentioned the low torque of the AAN/ABYat 1950rpm. I wasn’t feeling this, and it felt laggy until 3k, and then pulled, better than pre fry but not that much harder.

Then it developed a hesitation under load.

Tightened all the hoses, some appeared loose, and while I think it may have made a very small improvement, it was really hardly noticeable.

Still hesitated under load at approx. 3/4k rpm.

Swopped in a fresh RS2 MAF, no difference.

Swopped in a 1.8T syle coil set. Cured hesitation instantly. Very much worth the money, but I don’t like the look of them compared to having the original 20Vt lid on the engine. New original coils might suit me in the long run, but for now the individual coils are a winner from a practical point of view, as well as being plug and play with Error’s wiring kit. So hesitation gone and pulled cleanly all the way to the redline. Not sure if the later red coloured ones are better again on not ???

Car now felt fried and good, but still with a definite step in the boost at 3k. A bit slow to react below that.

Swopped in a new bypass valve and it boosted a good bit harder again. i.e. a worthwhile improvement over an old tired but ‘working’ bypass valve. This is a relatively inexpensive item to replace considering the extra poke and was certainly a noticeable improvement was gained. But here is the rub. When the valve was first fitted there was no improvement and I was disappointed, but after say 5 to 8 days of normal daily driving, I didn’t make notes, it suddenly was much better and improved as described above.

Weird but true, for me.

Still felt dead below 3k with the boost step, so decided to fit a new AAN wastegate frequency valve – 034 906 283 H – (Eaton – Made in Monaco). The ANN valve was either NLA or very dear or both, so ordered an S2 one – 034 906 283 K, which was much less expensive and available, the only difference is that the two side pipes at 3 o’clock pm and 9 o’clock pm are at a 90 degree angle compared to the same two pipes on the original 283 H valve. It would not pass concours, but still fits with no significant issues. It does not fit the rubber holder that is on an S6’s Michelin Man’s hose, but there is no rubber holder on an S2 ABY hose, so if it was a source of annoyance, maybe a ABY Michelin Man hose could be swopped in, anyway too much detail, and I digress.

Wasn’t expecting a sudden change and noticeable change, but was hoping though. What I found straightaway was that the car is smoother to drive and now boosts from 1950k rpm. And pulls hard / incessantly up to the red line and feels very much like it is fried. It feels like a ‘supercharged’ car now rather than a turbocharged car, as there is less lag and more low down pull, and so I suppose it’s more linear without the sudden boost of the turbo cutting in at 3k. It also seems smoother when one comes off the throttle from either the mid throttle or wot throttle position. Nicer to drive, more civilised, and quicker still in the real world.

Looking back, all the times I thought the engine was good / ok and running well, there was a number of gains to be had by changing out the components referred to above with brand new ones.

So the moral of the story is that while half of you have I5 cars running correctly, the other half may not, but don’t realise it.

While I could have put the car on a rolling road each time to determine any faults/changes/improvements. It would have been be way too costly, and also way too time consuming. No rolling road near me, no time, no money for same.

I could have fiddled around with VAG Com, but I don't have it.

So what I am suggesting is that people definitely consider replacing the bypass valve with a Bosch 280 145 710 N, and the waste gate frequency valve, even though you feel yours are working fine.

Do fit new ones and post your results up on this thread. While your results may differ, my car is way better and I'm chuffed with how it now runs. I’m now almost tempted to take it out to drive it for pleasure, rather than just because I need to go somewhere.

It might be too soon to say, but I also think that I am getting more miles to the tank, but my daily commute /routine has changed and I am not yet fully sure but I think it has improved significantly by maybe by 50 miles to the tank. But because I didn't take notes at each stage I cannot be 100% when this mpg improvement occurred, and exactly how much the improvement is.

Please post comments on your findings / experiences to date with your I5 20Vt, for others to share if you do decide to take the plunge and change out the above components, either at the one time or one after the other.

HTH someone.