So I've had a check engine light (Code P1128) on my 2001 TT for the past month and a half now. First, I visually inspected for boost leaks; none. Then, I decided to clean the MAF. Things seemed fine for about 50 miles, then it was back on. So finally yesterday I was frustrated and purchased a new MAF from the dealership. The car runs much better, but the light came back on (again).

Any suggestions? I can't seem to figure out what else this might be. Someone help

 

The O2 sensors and fuel injectors are another possible cause.

 

I would try the o2 sensor

 

Is there any possible way I could just flash this code for good?

 

P1128 is indicating a lean condition. Check your MAF.

 

he just said he replaced his MAF.
'visually inspected for boost leaks' entails what? Did you pressure test w/ soapy water? If not, you didn't inspect anything.

 

^ try injectors?

 

Well, the dealership claims this is what they did, but who knows if that's the truth (doing it myself would probably be the best route).

How would I know if the injectors are bad though? I don't want to replace those too and still have this problem lol. I don't know much of a performance difference, it's just that the check engine light is super annoying...

 

Hey! Same problem here. Cleaned the MAF, had light reset, came back on, oh, 5 miles later. Let me know if you get this cleared up. Thanks!

 

I have the same issue with my TT & have replaced the MAF & fixed 4 different vacuum leaks.....still hunting for the last one.
I bought a foot pump today & plan to bubble test for leaks tomorrow.
I suggest you get a vacuum gauge & see if the needle jumps around at idle....if it is rock steady then you have no leaks.
I had 3 leaks under the intake & just found another at the firewall underneath a heat shield going to the brake booster....they can be very sneaky.
Hope this helps a little....its something you can do yourself.
Good Luck,
Eric