Jaguar AJ-V8 Family (Gen III)

AJ126 / AJ133

Despite being six cylinders, the AJ126 is still considered part of the AJ-V8 family, as it is in essence a supercharged AJ133 with two fewer cylinders.

Problems

• Timing chain:
  • Through 2012, the engine used plastic timing chain guides. These have a tendency to fail, especially if the owner of the car followed the extended oil change intervals (rather than changing it every 5,000 miles, for example). Failure causes catastrophic engine damage. There are upgraded parts available, but they are not cheap to install. Model year 2013 and later supposedly are not susceptible to guide failure, or at least are less so.
  • Through 2012, the timing chain tensioners had a tendency to wear out and fail. Failure causes catastrophic engine damage. There are upgraded parts available. Model year 2013 and later supposedly are not susceptible to tensioner failure, or at least are less so.
• Water pumps