Jaguar/Land Rover V8 Engines

Jaguar/Land Rover V8 Engines

What makes this engine unique is the high-pressure fuel pumps are driven by the crankshaft using a chain that also turns the oil pump.

In 2008, Jaguar and Land Rover introduced the third generation of the AJ V8, or the AJ133. What set this 5.0L engine apart from the previous 4.0L and 4.2L versions was an increased displacement of five liters and direct injection. What makes this engine unique from other European V8s is the high-pressure fuel pumps are driven by the crankshaft using a chain that also turns the oil pump.

High-Pressure Pump

The AJ133 has two high-pressure fuel pumps mounted on the right-hand side of the engine block. The forward pump is number 1, and the rear pump is number 2. Each pump has a control valve that varies the fuel delivery amount by adjusting the timing of the engine. 

The pressure relief valve protects the high-pressure side of the system from excessive pressure if there is a failure of the fuel metering valve. The nominal maximum operating pressure of the pumps is 2176 psi. The injectors deliver the fuel mass directly to the combustion chamber. The high-pressure fuel lines are connected together before they feed the right rail. 


  • Before any work is carried out on the high-pressure fuel system, the system must be depressurized. This can be performed with a scan tool to disable the in-tank pump and allowing the engine to run until it stops. 
  • The fuel pump fasteners must be tightened evenly and according to the service procedures. Failure to follow the set procedure will result in the mounting flange being stressed, which will lead to failure of the pump.
  • To avoid unnecessary noise being transmitted to the cabin, the pumps are equipped with covers, which must always be refitted correctly, if removed.


The injectors are indexed like some spark plugs. The injectors have six spray beams. Two beams point below the spark plug, and the other four beams distribute fuel to the rest of the cylinder. The injectors operate using a two-stage power supply from the ECM. The initial trigger for the injectors is 65 volts. Once the trigger reaches a current level of 11 amps, the power supply is switched to battery voltage to keep the injector open. 

more TIPS

  • The Teflon seals must replaced if the injector is removed from the engine. 
  • Do not contaminate the Teflon seals with oil or grease to aid the assembly of the injectors to the engine.
  • Always clean injector bores before fitting fuel injectors.
  • The spark plugs should have been removed prior to pulling out the injectors with the slide hammer tool. 
  • Place a clean cap over the O-ring end of the injector to prevent contamination by dirt.
  • The fuel rail and fuel injectors have built-in non-serviceable filters.
  • Always reinstall injectors in the same location from which they were removed.
  • If the fuel rails are removed, special tools must be used to align the fuel rail to injector when refitting. If this procedure is not carried out, the injector is then subjected to excessive side-loading which can cause the injector seal to become overheated.

In-Tank Pump

The AJ133 uses a returnless fuel system. The system pressure is maintained at a constant 59 psi. The fuel is supplied to the high-pressure fuel pumps from a fuel pump fitted within the fuel tank. Opening a vehicle door will cause the fuel pump relay to be activated for 3- to 5-seconds.

Common Problems

There are no major issues with the fuel system with either reported problems or TSBs. The only TSB for the fuels system warns about the use of low-quality fuels that lack enough detergent. While there have not been widespread reports of carbon deposits, regular induction cleaning services and in-tank treatments can reduce deposits on high-mileage engines.

You May Also Like

The Latest on Lifters

Advancements in technology, as well as modern testing and research is constantly evolving to make lifters better.

When it comes to lifters, there will always be the traditional questions of solid versus hydraulic and flat tappet versus roller. Some of the answers may remain the same, but advancements in lifter and manufacturing technology, as well as modern testing and research is constantly evolving to make these components better. We took a look at today’s lifters, the technology behind them and some tips from the experts.

Understanding Underhood Parts for Hybrids

Anything that can happen to an ICE in a standard vehicle can happen to an ICE in a hybrid.

Engine Building 102 – Building The Perfect Top End

Join Doug Kaufman and the experts at Summit Racing for a livestream on November 29 at 1PM EST.

Taking The Guesswork Out Of Building Rotating Assemblies

Rotating assemblies can be a guessing game as you struggle to find the right option for your project.

Understanding Fuel Injection

Though many different terms have been used for the technology, it really just comes down to indirect or direct.

Other Posts

Electronic Throttle Body Service

On most systems, idle speed is completely controlled by the throttle plate angle.

Adapting Sensors For Changing Inputs

Let’s focus our attention today on one small facet of the technology inside modern vehicles: Adaptations.

Carbon Deposits In Direct Injection Engines

The primary cause of these problems is that fuel and added detergents are not hitting the back of the intake valves.

Smart Battery Management

Most modern systems will measure the internal resistance, which changes the capacity of the battery & how it charges.