JettaRedII

I have a 2004 Audi TT 225 with a little over 239,000 miles. A couple of weeks ago, I got a CEL with a lean code. I tried a 4 bar FPR and that gave me a rich code. I replaced the fuel filter. So I decided to trouble shoot using recommendations on the Ross-Tech sight--checking for vacuum leaks, etc. Today I check vacuum hoses, the combi valve, etc. and find nothing out of place. I clear the code and rescan. Immediately, I get nine codes and both the CEL and traction control light come on. Here are the nine codes:

17861/P1453 - Exhaust Gas Temp Sensor 1 (G235): Open or Short to Plus
17833/P1425 - EVAP Purge Valve (N80): Short to Ground
17525/P1117 - Oxygen (Lambda) Sensor Heating Circuit: B1 S2: Short to Ground
17876/P1468 - EVAP Canister Solenoid Valve 2 (N115): Short to Ground
17843/P1435 - Secondary Air Pump Relay (J299): Short to Ground
17829/P1421 - Secondary Air Injection Solenoid Valve (N112): Short to Ground
17880/P1472 - EVAP Leak Detection Pump: Short to Ground
17522/P1114 - Oxygen (Lambda) Sensor: B1 S2: Internal Resistance too High
16486/P0102 - Mass Air Flow Sensor (MAF/G70): Signal too Low

This is so weird. Any ideas? Thx

JettaRedII

Problem solved, but not easily.

Turned out to be a bad MAF that was shorting and blowing fuse 43. Fuse 43 supplies power to all the items that threw codes. through a process of elimination, I was able to isolate the MAF. When the MAF was connected, fuse 43 blew at start. When it was not, the fuse didn't blow. You definitely need the wiring diagrams to troubleshoot a problem like this.

J. Patterson

Excellent work!