JHB

Hi,

A couple of months ago I bought a 1999 TT225Q Coupe. The car had been chipped, but I don't know by whom.

I have experienced a couple of problems. After I had had the car in to check why the air condition wasn't working the car behaved very strange. When I first drove of it was almost impossible to drive. It didn't pull evenly at all, don't know if it is the lack of gas or air that's causing this? (don't know the english word for this ) And when reaching 4500-5000rpm the turbo kicked in big time and pulled me back into the seats. Needless to say I went back to the shop (which is an authorized VAG dealer) and asked them what the hell they've been doing with my car. They claimed that they've only done a diagnostic check to look for fault codes. They saw that the turbopressure had an error, but this might be because it's been chiped? Anyway they were less than helpful in trying to figure out what was wrong, and when I said it's been chipped they said, we'll there you have it, it's probalby the chip thats' broken or a pin missing or something. Yeah right! If the chip is broken or a pin is missing then I wouldn't even get it started. So I left pissed off, hoping that things perhaps would be better after driving around a while. And it did, the next day it was almost back to normal.

Any idea what happened to my car?

I said almost normal, it still has a few strange "features". When doing full throttle from 2nd gear around or just under 3000rpm it pulls fine. The turbo kicks in at around 3000 and pulls evenly all the way to 6000rpm. But if i for example drive in 2nd gear at around 4000rpm and then floor it, nothing happens for a second or two, and the turbo kick in big time at around 4500-5000. It's like a turbolag, but surely this shouldn't be 2 seconds? I mean from around 3000rpm the turbo kicks in almost immediatly. Also in first gear it cuts at about 4500rpm when flooring it?

I think the pressure of the chip is too high, i haven't messaureed it yet. The previous owner claimed it to have almost 400NM(!). I'm not sure if the pressure is causing this, but one of the hoses from (to?) the intercooler broke. I had to cut away about 2 inches to connect it again. The hose is the small one from then aluminum pipe which is just under the swaybar. It connects to some sensors i think which is again connected the the air intake.
What function has this hose?
After I had to cut a bit on this hose the car now pulle very unevenly when not aplliing full throttle. Especially around the area where the turbo is supposed to kick in. Full throttle is no problem.

Any ideas?? I'm not too experienced with the turbo engines, but could it be some sensors thats broken?

Also where can i find the ECU in the TT. I want to check if I can find out who the chipmanufacturer are.

Any answers, thoughts would be much appreicated.

jon

MOBlueTT

Here are some thoughts, not necessarily in priority order.
1) Find out the exact error code #, the VAG experts will have some ideas
2) Turbo lag can be hard to ID, the main issues you will hear about or search about are the DV (diverter valve)- likely to be at least part of your problem unless replaced recently, the N75 valve(usually regarding surging) and the MAF sensor (mass air flow)- which can be cleaned
3) How many miles?
4) Ask the previous owner, if you can, who's chip and when they bought it (to estimate what version you may have) The "chip" is added INSIDE the ECU - so after you took it out, you would have to take the cover off and then ID the part - probably take a pix and ask the forum who's chip it is

Let's see what others have to say...

JustJeff

Sounds like you may have a bad DV.<ul><li><a href="http://home.attbi.com/~ttbipes/eculoc.html">ECU Location</a></li></ul>

RockeTT City

I not sure about your problem, but the chip missing pins is the funniest y heard for long time!

JustJeff

Not *my* problem, think you got this under the wrong link.

JHB

1) Yes, I will try and do that the next time I'm at VAG.
2) The DV has been replaced with a new aluminum DV. I don't think thats the problem.
3) about 37K miles
4) I will take a look at the ECU. Thanks for the URL Jeff!
5) Also noticed some oil in the pipe connecting the two intercoolers yesterday when I changed oil. I don't think there's supposed to be any oil in this pipe? It was definatly on the inside of the pipe.

Jon