I took my TT to the repair shop after getting a CEL. Before I took it to the shop, I ran the vagtool diagnostic and got these codes:
Address 01: Engine
Controller: 8N0 906 018 AT
Component: 1.8L R4/5VT G 0003
Coding: 06710
Shop #: WSC 01236
2 Faults Found:
17544 - Fuel Trim: Bank 1 (Add): System too Lean
P1136 - 35-00 - -
17884 - EVAP Leak Detection Pump: Insufficient Vacuum
P1476 - 35-00 - -
Readiness: 0000 0000


Now, the people at the shop told me that my boost gauge is pulling vaccum out of the system and is causing the CEL. I have the boost gauge tied into the FPR just like everyone else, so could it be causing these problems? Also, the shop says that the vacuum pump has probably gone bad, but i've heard that not tightening the gas cap can cause the problem as well. In addition, they say that the MAF is reading below spec, and when I tried to tell them to clean it they told me that if they clean it, it wont work properly. They said cleaning it will never help and a new part has to be ordered. Somehow I find that hard to believe considering what ive read over in these forums

What do you guys think? Give me some advice please

 

please take your car back and give them nothing for their time. they dont know anything. Clean your maf yourself.

the boost gauge isnt hurting anything, otherwise 90+% of the people with turbo cars would have problems. What is your vacuum when warm? should be around 20in hg when at idle. If so you are fine, if not, you have a vac leak somewhere. You may have a bad o2 sensor and a vac leak around the egr, if your car takes a long time to get warm then you do (my vac line was disconnected and i didnt know it and it took about 20mins to get warmed up, now it takes less than 5)

 

yeah unfortunately they charged 150 for taking a look at the car, and im going to pick it up tomorrow..

I figured they were wrong about the boost gauge.. My vacuum is around 20 inhg at idle so that sounds about right. My car doesnt take a while to warm up though, it warms up fine.

The thing is, when i ran the vag com tool it said the engine was under 15% load at idle. Plus, when i start the car it idles high sometimes.. In addition, sometimes when i let off the throttle, the RPMs stick for half a second and then start dropping.

 

whats the egr?

 

I would clean your MAF and replace the 02 sensor and then see how it goes from there.

 

I have the same issue, my MAF is brand new, but its throwing a CEL - I need to replace my O2 sensor and it will fix the problem.

 

Cleaning your MAF will only get you so far. Eventually you'll need a new one.

A new MAF makes much more of a difference in performance then a recently cleaned one. I got away with cleaning mine twice in 4mos before giving up and buying a new one. I'm happy I bought the new one.

 

exhaust gas recirculation. It is used to get the engine up to temp and for emissions.

 

some companies also make egr block off plates to totally get rid of the egr system.....not sure on the TT but the Supra MkIV didnt even come with an egr system in Japan...but for the emissions here in the USA they did...i forget the website but i know a company makes a egr block off plate for our TTs.....i've been looking into the pos and neg effects of blocking it off....also dont anyone who has done this to an Audi...not sure if i wanna be the tester on this one.

 

its just another 1.8t. The only reason to get rid of it is for people that dont have emissions and want to shave everything that isnt neccisary off the car: egr, 2nd air pump, a/c, and so on.

but its intergrated engineering plate sold by 20squared tuning. Votex has plenty of how tos.