About two weeks ago the performance of my car started to fall off. I have a boost
gauge installed and noticed that boost no longer hit 19 psi (Garrett 30b) and was slowly
creeping further and further down. I know a pretty good deal about these engines so I
got to work. I determined that the problem was the recirculation (blowoff) valve
because of the very loud shwoooooooooosh sound that would come on anywhere after
half-throttle. If the valve were to break, this is exactly what would happen... all of the
boost would leak out. So I ordered a replacement and installed it... result = worse. The
first time I floored it the car hesitated severely and boost fluctuated between 15 psi
and 12 psi. After a couple of miles though, the boost evened out and now hits a max at
11 psi. The car is a dog and that leaking boost sound is still present. I have checked
the following and come up w/ no results...

Leaks in piping - I checked every hose that I could find. I couldn't feel or hear any
leaks.

Every thing I could think of checking w/ VW Tool. Came up w/ no faults or strange
numbers except that the computer has been pulling -18.8% of fuel out of the trim. I
assume that this just happened because the engine was recieving very little air
(because of the leak) and as a result had to cut out fuel.

So, if anybody has any ideas of what to check please send them my way (or where I
should check for leaks). I really don't want to take the car to the dealer unless I
absolutely can't find the problem. I know that the K04 still works because I am still
getting possitive PSI at the manifold. The only thing I haven't checked yet are the
spark plugs which I'll do later today.

TIA,<p>Dan
99 1.8TQMSX K04 Santorin
<img src="http://pictureposter.audiworld.com/AudiWorldPics/2000/danh-sig.jpg">
<a href="http://a4q.tripod.com">a4q.tripod.com</a> -- My Website (way out of date)

 

I am not exactly sure what "limp home" mode does, but I know it cuts performance off.

I have thought about getting a K04 after my 03 dies. How does it feel? Do you have a chip along with that?

Where did you purchase the K04?<p>---- '98 A4 1.8T QMS ----