Audi A8: 4.2 FSI V8 Cam Follower and HPFP Drive Wear

The 4.2-litre FSI V8 (BFM, CAUA, and related codes, in D3 and D4 A8) shares the high-pressure fuel pump cam follower wear defect documented across the entire Audi/VW FSI engine family. The mechanical HPFP is driven by a dedicated lobe on the intake camshaft via a small roller follower. This follower is under-lubricated and wears through rapidly — typically at 40,000-80,000 km on unmonitored cars — eventually destroying the camshaft lobe. The repair window is narrow and the follower must be inspected at every oil change. Once camshaft lobe damage occurs, the repair cost escalates dramatically to include camshaft replacement. This is one of the most documented FSI failure modes across Audi forums globally.

• Hard starting or extended cranking before the engine fires
• Misfires at idle or under light load
• Lean mixture fault codes (P0171, P0174)
• Ticking noise from top of engine near the high-pressure fuel pump
• Loss of fuel pressure on live data scan

1. 1

   Ask to see evidence of cam follower inspection records — this is a standard check item on any informed Audi specialist service.

2. 2

   Check for fuel pressure codes.

3. 3

   Review oil change intervals — extended intervals significantly accelerate follower wear.

4. 4

   If a workshop inspection is possible: Remove the HPFP (quick job from the top of the engine) to inspect the follower for flat-spotting or through-wear.

Parts involved: High-pressure fuel pump.

$350 to $6,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the cam follower beneath the high-pressure fuel pump been inspected recently?”
• “When was it last replaced, and what was the wear condition at inspection?”
• “Has the vehicle experienced hard starting or misfires?”
• “What oil change interval was followed — strict short intervals or extended?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.