on my 2001 A4 1.8T i'm having a problem with boost, i have a revo chip, the boost spikes to 20psi and starts droping and it only holds at aound 11-12 psi.

Replaced the N75J valve, and did not improve, after replacing the valve took the car for a boot to see what the results were and when i pulled back into the garage looked under the hood and when i looked the exhaust manifold and turbo were glowing red..."i did beat on the car on my test drive but i don't think that its normal for it to get that hot".

any thoughts on this?



thank you

 

^ Pretty normal with a chip and a k03, you might want to look into cooling of your car after driving it hard

 

What are you reading at idle? (in Hg) Should be around -20...

As it stands without knowing that... it sounds like you have a major boost leak.. boost should only settle ~2-3 psi below spike...Start checking all hoses and the vac lines...

 

at idle it reads aroun -18- -20hg, so with these reading i don't believe that i have a vac leak, what is really making me panic was seing my manifold and turbo turning red hot...i'm quite sure that it's not normal, but please correct me if i'm wrong, if anything was to get that hot i would think that it would be either the cat and down pipe but not the exhaust manifold.

 

You stand corrected ! The little K03 and mani will glow red after a nice run !! IN order to avoid turbo damage, just make sure you drive the car "mildly" for several minutes after pushing it or let it idle for a few minutes while parked before shutting it down.

 

and what would you say to the boost droping so low, at 3000rpm i'm hiting full boost 18-20psi and then it drops to 10-12psi

 

I'm a WD40 duct tape kinda guy (fortunately, I have a great mechanic). My money is on a boost leak though ... have you vagged the car to see if there are any codes? Can you pressure test it to check for a boost leak ? Sorry that I can't be of more help

 

It just ocurred to me that perhaps you've got a bad DV?? Any odd noises like a honking sound ?

 

ya i vagged the car, and there were no codes at all

 

that was one of the things that came to mind...even though my dv is new but it could be, i need to swap it with a known good dv and try it...no way i can try it with the stock dv, i'll blow it right out of the car at 20psi