P0377moderate severityPowertrain
Timing Reference High Resolution Signal B Too Few Pulses
on 2014 Audi Q7 3.0L Supercharged V6 · AWD
What this code means
The PCM received fewer high resolution timing pulses than expected on signal B. This may indicate a missing tooth on the tone ring or sensor fault.
Symptoms
- Check engine light on
- Poor performance
- Rough idle or misfire
Common causes
- Damaged or worn tone ring
- Faulty timing sensor
- Excessive air gap
- Wiring fault
Diagnostic steps
- Retrieve stored codes
- Inspect tone ring for missing teeth
- Measure sensor air gap
- Replace sensor if defective
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