P054A Cold Start B Camshaft Position Timing Over-Advanced Bank 1
Camshaft B is the exhaust camshaft. During catalyst heating after a cold start some engines set it to a specific position; CARB requires such commanded elements to be monitored with their own codes, separate from the normal cam codes. Ford watches the deviation with an averaged variance index for each direction; GM (Saab 9-4X V6) uses only the retard codes, above 6° for 1 s or 4 s cumulative, type B. The commonest cause is oil pressure building too slowly when cold. P054A means bank 1 was too far advanced. Mercedes (M276) traces it to slow oil pressure – 1 bar should be reached after about 3 s; Audi (Q5 3.2) and VW (Atlas 3.6 and 2.0 T) fixed it by software.
Likely causes
Symptoms
- Check engine light on, usually without noticeable symptom
- Brief rattle on cold start
- Rough idle while warming up
Repair estimate
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
Related codes
References: newtonnet.co.uk, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.