I am boosting to 11PSI in a 180 QC but I really can't feel the turbo all that much. It feels like it kind of kicks in at 4k, but something doesnt feel right.

I had a new DP put on and a magnaflow cat and that is it for recent work. The car was having this problem prior to the work, and I was hoping replacing the bad flex pipe would fix the issue - but it isnt.

What could cause this symptom?

I boost to 11psi
I idle at 18 hg and it is rough because it spikes to 16 psi every few seconds and you can hear the engine idle rough.

Would I still boost to 11 psi with a vacuum leak? What psi should it be holding at and for how long?

 

quick correction, you're probably idling at 18"Hg, not PSI. Vac is measured in inches of mercury.

That out of the way, clean your MAF. Its a good safe starting point, and probably something worth doing once in a while anyway. While you're in town getting MAF cleaner, get some PVC and a air fitting, and make a intake pressure tester. If you're only hitting 11psi, it kinda sounds like you might have a leak somewhere.

 

Where did you get the dp and how much.

 

That was a typo on my part i know its hg. MAF is new (2 months). I also have a pressure tester and couldnt find a leak. Maybe it is too small for me to hear? :-(

 

dp came from blacktrax. i got it on vortex from a member. 2.5" ID to magnaflow catback is 225 duals. sounds nice and deep now.

 

I don't know much about Blacktrax products. I was under the impression that they made parts mostly for hondas and acuras. Did you get the DP installed by a shop, or diy? I always thunked quattro 180 DP's had to be custom due to the k03 flang. More info on this please!

 

i had a shop do the install. there isnt much more info on it. I have a few threads on audiworld, and i go by the same username. you can also search vortex and i have the same name there. there was a thread for the DP a while back.

Sorry if i'm not being more forthcoming - I am really trying to get the issue with my car fixed as detailed in the thread topic and not take the thread off topic.

 

The leak was my best guess, MAF was number two. Even if its new, theres still a chance your MAF is bad, until I can get a better understanding of your situation, I'm gonna have to keep my money on that. Try unplugging it and running the car a bit, see if theres any difference.

 

could also be the n75 dying. Those have been known to cause headaches when they become problematic.

 

well, it could be a pinhole vacuum leak, but i don't know. Every hose i looked at looks fine.

When i check for the leaks, I am supposed to plug the pcv system right? Where is the best place to plug it?

I want to make sure i am checking for the leak correctly. From what i read at steve's site, it said that the system will bleed pressure at the TB, and i'll hear bubbles from my oil fill cap. That is correct, right?


The maf seems fine. Is there anything I can do to verify the N75 going bad?