Car passed emmision test last week...Would like to determine the root cause before repairing...don't want to just replace the cats and the o2 sensors...Where can i get an accurate diagnosis?
cel with p0421 and 431...how can i troubleshoot and determine the root cause on 2003 Audi A4 Quattro
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Recent Audi A4 Quattro Questions
- How much will cost to do the timing chain extensior?
- Is there an gasket right below the coil packs on a 2.8
- Gas leak, put new fuel rail an injectors in an still leaking gas
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- extended warranty - I just bought my leased2014 A4 and trying to decide whether
2003 Audi A4 Quattro Estimates
- Differential Fluid Replacement - Rear ($58 - 106) in Norwood, MO
- Starter Replacement ($347 - 553) in Deer Lodge, MT
- Engine Overheating Diagnosis ($88 - 111) in Huntsville, TN
- 100,000 Mile Service ($224 - 323) in Cayce, SC
- Steering Knuckle Replacement ($950 - 1,001) in Belfast, NY
- HVAC Blend Door Actuator Replacement ($135 - 147) in Howard, CO