# '01 Audi TT 225 Low Power/boost/MAF readings showing on VAG-COM



## Currancchs (Feb 24, 2011)

*'01 Audi TT 225 Low Power/boost/MAF readings showing on VAG-COM --- Solved*

Hi, this is my first post here, but I have trolled these forums for years now, and thank everyone who posts here for their invaluable advice in keeping my VW, and now Audi running over the years. As a student I can't afford to always be taking my car to the mechanics, and enjoy the satisfaction of doing something right/myself anyhow. Now for my most recent issue. I just picked up the 2001 Audi TT225Q about a month ago, and it didn't feel as powerful as when on the test drive, although I could be mistaken. I checked peak horsepower and torque with a third gear WOT run with Vag-com and it showed slightly less than 180HP Peak, and around the same for torque. I then looked into timing pull (Slightly less than 5 degrees peak), Boost (Peaks at almost 12 psi, should be 15 I believe), MAF (peak = 160 g/s) and N75 duty cycle (Starts out at ~95%, but drops to low 70%'s. I have no idea why the numbers are low across the board, but I suspect DV, boost leak, or dirty MAF. There are no codes being displayed currently, although Vag-com shows intermittent O2/MAF issues. I will start by cleaning the MAF and taking some new logs, but any advice would be greatly appreciated. If you guys suspect DV, N75, etc. what have you had luck replacing the stock one with, not opposed to replacing with another stock part, but if there is a better cheaper solution out there I would be all ears. Note: The car is bone stock, not chipped (That I know of, but it certainly doesn't feel it, although for 180HP it certainly pulls well).

P.s. If anybody would like to let me know how to post the logs, they are charted in excel, tried copying and pasting here to no avail.


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SOLVED

The problem was a combination of bad primary O2 and a massive vacuum/boost leak coming from the brake booster line as it runs under the front portion of the intake manifold, blew as soon as pressurized (and no, it was not over pressurized) lean fuel trim caused check engine light 5 minutes before pressure test!


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## Currancchs (Feb 24, 2011)

*Fuel Trim Information*

Hi, forgot to include I also looked at fuel trim information, and idle was around 4.6%, while part throttle was ~7.8%, let me know what other information would be helpful! Thanks again!


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## 20v master (May 7, 2009)

Fuel trims aren't way out of spec, but getting close to the +/- 10% acceptable limits. Best place to start would be a pressure test to find any and all vacuum leaks, clean the MAF and throttle body 
(and align the throttle), and go from there.


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## Currancchs (Feb 24, 2011)

*Website with vag-com graphs up*

Hi guys, just set up a quick website to host the file containing all of the logged data and graphs mentioned in the previous post (Have to click on excel file link though, no time to post the graphs themselves tonight, maybe tomorrow). Here is the link. Thank you in advance for your assistance. 

http://currancchs.dyndns.org/~MC


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## Currancchs (Feb 24, 2011)

*Thanks!*

I will be working on the car this sunday (Changing trans. fluid, haldex clutch fluid/filter, and diff. fluid) and will try what you recommend. I'll let you know the result and post some new logs after I'm done. Thanks!


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