Help to find cause of emissions diagnostic codes?
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AudiWorld Newcomer
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Help to find cause of emissions diagnostic codes?
Hi all,
I have a MK1 TT 2005 1.8T 180BHP Quattro coupe and I'd appreciate some help in finding the cause of an emissions problem with the car.
Here's the situation:
- The car came close to failing the emissions test of the National Car Test scheme.
- The engine intermittently runs a little rough and the power can dip slightly (nothing significant, but very clearly noticeable).
- The check engine light comes on intermittently, and the OBD reports codes P1176 and P0420.
I've read that there are two oxygen sensors, one on the upstream side of the the catalytic convertor, and one on the downstream side. The difference in values between these two sensors indicates how well the catalytic convertor is performing.
I've also read that these problems can be caused by a faulty oxygen sensor, or a faulty catalytic convertor, or a hole in the exhaust system (which messes up the air flow in the exhaust).
Does anyone have any experience of this kind of emissions problem, or with these particular error codes, or any other thoughts on what could be causing the problem?
Many thanks!
Andy_C_
I have a MK1 TT 2005 1.8T 180BHP Quattro coupe and I'd appreciate some help in finding the cause of an emissions problem with the car.
Here's the situation:
- The car came close to failing the emissions test of the National Car Test scheme.
- The engine intermittently runs a little rough and the power can dip slightly (nothing significant, but very clearly noticeable).
- The check engine light comes on intermittently, and the OBD reports codes P1176 and P0420.
P1176: OBDII: Cam Calibration Fault; Audi: O2 Correction Behind Catalyst,B1 Limit Attained
P0420: OBDII: Catalytic converter system, bank 1 - efficiency below threshold; Audi: Catalyst System Low Efficiency
I've read that there are two oxygen sensors, one on the upstream side of the the catalytic convertor, and one on the downstream side. The difference in values between these two sensors indicates how well the catalytic convertor is performing.
I've also read that these problems can be caused by a faulty oxygen sensor, or a faulty catalytic convertor, or a hole in the exhaust system (which messes up the air flow in the exhaust).
Does anyone have any experience of this kind of emissions problem, or with these particular error codes, or any other thoughts on what could be causing the problem?
Many thanks!
Andy_C_
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