4.2 V8 40V (ARS/ASG/AQJ/ANK/BAS/BAT/BBK) vs 5.2 FSI V10
Side-by-side reliability comparison
Higher reliability score
5.2 FSI V10
BUY
83/100
+23 points over 4.2 V8 40V (ARS/ASG/AQJ/ANK/BAS/BAT/BBK)
0
/ 100
CAUTION
4.2 V8 40V (ARS/ASG/AQJ/ANK/BAS/BAT/BBK)
Audi
0
/ 100
BUY
5.2 FSI V10
Audi
Specifications
4.2 V8 40V (ARS/ASG/AQJ/ANK/BAS/BAT/BBK)
5.2 FSI V10
Brand
Audi
Audi
Verdict
CAUTION
BUY
Reliability
60
83
Years
1999--2009
2006--2015
Displacement
4163 cc
5204 cc
Layout
V8
V10
Type
Petrol Na
Petrol Na
Power
299--344 hp
435--560 hp
Known Issues
1
3
Total Risk Cost
€1,380--€3,220
€370--€740
Character
4.2 V8 40V (ARS/ASG/AQJ/ANK/BAS/BAT/BBK)
"The 40-valve port-injection 4.2 V8 of the S4 B6/B7, S6 C5 and A6 4.2. Glorious sound, but the plastic guides and tensioners of the rear-mounted timing chains break up with age and heat - an engine-out job, and if the chain jumps a tooth the valves meet the pistons. Listen to a cold start and look for proof of the chain job."
5.2 FSI V10
"Naturally aspirated 5.2 direct-injection V10 of the S6 C6, S8 D3 and first-generation R8 V10. No engine recall and few complaints, but it is an expensive engine to keep: intake valves coke up like all FSI engines and need periodic walnut cleaning, and the timing chains sit at the back, so chain or guide work means taking the engine out. Buy with full service history."
Issues Comparison
4.2 V8 40V (ARS/ASG/AQJ/ANK/BAS/BAT/BBK) 1
◆ CRITICAL
Plastic timing-chain guides and tensioner break up - engine-out repair
5.2 FSI V10 3
▲ HIGH
Timing chain and guide wear (rear-mounted, engine-out job)
● MODERATE
Intake-valve carbon build-up (direct injection)
○ MINOR
Ignition coil failure (10 coils)