2012 Jaguar XJ Problems: 11 Known Issues

On the 2011-2019 Jaguar XJ 3.0L V6 diesel (306DT / AJ-V6D), owners of XJ 3.0D models describe sudden bottom-end failures: the oil pressure warning comes on, a knocking noise starts and the car goes into limp mode. In the reported cases a main or rod bearing had spun, or the crankshaft had snapped. Diesel engine rebuild specialists describe the same failure on this engine and link it to bearing shells that can move and block their oil feed. Applies to: Only XJ models with the 3.0-litre V6 diesel (306DT), sold as the XJ 3.0D outside North America. It does not apply to the 3.0 supercharged petrol V6 or the 5.0 V8. Owners report it on cars of different ages and mileages, including a 2016 XJ 3.0D Portfolio.

On the 2010-2015 Jaguar XJ, the 5.0-litre AJ133 V8 fitted to the X351 has a widely documented timing drive weakness that has nothing to do with the earlier 4.2 AJ34's plastic tensioner story — the X350's 4.2 already ran metal tensioners and Morse chains, and merging the two engines' histories is the standard error on this nameplate. On the AJ133, the hydraulic tensioner's hardened steel plunger bears against a guide rail with a soft aluminium core and a plastic wear face. The plunger cuts a groove into that face; the ratchet that is supposed to hold tension with the engine off then cannot, and the chain slaps on start-up before oil pressure builds. There are no fault codes at the rattle stage, which is exactly why it gets ignored. Left alone, the chain can jump a tooth — giving a restricted-performance warning and misfire codes — or break, which on this interference engine destroys it. Jaguar Land Rover revised the timing components progressively, with the setup substantially reworked by around 2015-2016, so late facelift cars are lower risk than early ones.

On the 2010-2019 Jaguar XJ, owners of 5.0 supercharged V8 cars describe a whine or grinding noise from the supercharger that rises with engine speed, sounding like a worn wheel bearing, and in some cases play in the supercharger pulley. They trace it to worn bearings in the supercharger snout (nose), which owners describe as sealed and not serviceable. Jaguar's bulletin for 2010-2014 XJs tells technicians to replace the supercharger if the pulley feels rough when turned or there is excessive whine. This is a different fault from the supercharger isolator rattle. Applies to: Only XJ models with the 5.0-litre supercharged V8 (XJ and XJL Supercharged, XJR, Supersport, XJR575). It does not apply to the 3.0 supercharged V6 or diesel models. Jaguar's bulletin covers 2010-2014 cars; reports on later years come from owners.

On the 2010-2014 Jaguar XJ 5.0L AJ133 supercharged V8, a separate component and a separate failure from supercharger nose cone bearing wear: the AJ133 supercharger drive uses a spring-loaded torsional isolator on the blower's nose pulley to damp driveline shock. The end of the original spring bears directly against plastic, and over time the spring wears grooves into its support shaft. The resulting backlash produces a loud, irregular clattering that owners consistently describe as marbles rattling in a tin can — loudest at idle, on overrun, and as the engine shuts down. It is easily confused with timing chain rattle, but this one is present at hot idle rather than only on cold start-up. Jaguar Land Rover issued Technical Bulletin JTB00349v2 covering 2010-2014 model year X351 XJ vehicles with the 5.0-litre supercharged V8, and released a revised isolator whose spring end seats in a metal cup instead of against plastic. Owners report onset from around 50,000 miles.

On the 2010-2019 Jaguar XJ, owners on XJ (X351) forums describe engine oil leaking from the brake vacuum pump, which the engine drives at the front of the engine on the 3.0 supercharged V6 and 5.0 V8. Owners and specialist shops say the pump's seals degrade over time and let oil seep from the pump's mounting flange or body seam, leaving oil residue on the engine and drips underneath. One owner reports oil from the pump dripping onto the alternator. Applies to: Owner reports from 2010-2019 Jaguar XJ (X351) with the 3.0 supercharged V6 or 5.0 V8, which includes the 2016 XJ R-Sport 3.0 supercharged V6. This is not a recall or bulletin; not every car leaks.

On the 2010-2019 Jaguar XJ, owners on XJ (X351) forums describe 'Air Suspension Fault' messages, a compressor that runs frequently or gets hot, and the car sitting low. Owners say the compressor itself is often not the root cause: a leaking air spring makes it run constantly until it wears out, and a sticking compressor relay can burn out a replacement compressor. Applies to: Owner reports from 2010-2019 Jaguar XJ (X351), which includes the 2016 XJ R-Sport. This is not a recall or bulletin.

On the 2004-2012 Jaguar XJ, the XJ suffers from cascading electrical faults caused by body control module (BCM) software glitches and CAN bus communication errors. Phantom warning lights, inoperative features, and intermittent failures across multiple systems are common, especially after battery disconnection or jump-starting.

On the 2010-2019 Jaguar XJ 3.0 V6 supercharged AJ126, owners on XJ (X351) forums with the 3.0 supercharged V6 describe coolant loss traced to the water pump (at its weep hole or the seal behind the pulley) or to plastic coolant pipes, including a crossover pipe, that sit underneath the supercharger. Owners note that the engine undertray can trap a slow leak and engine heat can evaporate it, so coolant may go missing without an obvious drip. Applies to: Owner reports from 2010-2019 Jaguar XJ (X351) with the supercharged 3.0 V6, which includes the 2016 XJ R-Sport 3.0 supercharged V6. This is not a recall.

On the 2010-2015 Jaguar XJ, the X351 uses the JaguarDrive rotary selector that rises out of the centre console when the engine starts and retracts when it shuts down. The mechanism that lifts the dial fails, leaving the selector stuck flush in the console. Because gear selection is by-wire through that dial, a selector that will not rise means the car cannot be shifted out of Park — it is drivable-adjacent but immobile, and it strands owners in car parks and on driveways. Early symptoms are intermittent: the dial rises on the second start attempt, or rises then immediately drops back down, which owners dismiss as a quirk until it fails outright. The same rotary selector design is shared with the XF and XK of the period, which is why the fault has such a large documented owner base.

On the 2010-2019 Jaguar XJ, owners on XJ (X351) forums report misting inside the LED tail lamps and, in some cars, water collecting in the bottom of the lamp. Owners say light misting can be normal, noting the owner manual addresses it, because the LEDs run too cool to dry the housing. Standing water is different: owners trace it to a leak, most often a hairline crack or opening along the welded seam between the clear and red sections of the lamp housing. Applies to: Owner reports from 2010-2019 Jaguar XJ (X351), which includes the 2016 XJ R-Sport. This is not a recall or bulletin.

On the 2010-2019 Jaguar XJ, owners on XJ (X351) forums describe one or both of the powered fabric sunblinds under the panoramic roof stopping partway, jamming, sagging or refusing to move, sometimes with a thumping, clicking or whirring motor. Owners point to broken plastic guide clips or the blind coming detached from its sliders, and in some cases a failed blind motor. Applies to: Owner reports from 2010-2019 Jaguar XJ (X351) with the panoramic roof, which includes the 2016 XJ R-Sport when so equipped. This is not a recall or bulletin.