A list of Common Faults

All vehicles with Common Rail Systems

Fault Will not start/difficult to start.
Cause Failed crankshaft sensor/High back leakage past injectors or split PCV seal
Repair Crank Sensor/Test Injectors/Replace seal on P.C.V.

All vehicles equipped with Denso Common Rail System

Fault Loss of power and/or engine stalls
Cause Failure of the P.C.V. (Pressure Control Valve)
Repair Replace P.C.V. (No pump removal required)

All vehicles equiped with Bosch Common Rail (CP1)

Fault Fuel Leak from high pressure pump
Cause Deterioration of seals caused by bio-fuels.
Repair Replacement of seals (pump removal required)


Fault Cutting out at idle
Cause Defective pump control unit
Repair Replacement control unit (Pump removal required)

Ford Transit 2.0 & 2.4 (Bosch VP system)

Fault Fuel Solenoid valve leaking
Cause Road salt attacks the sealant around solenoid.
Repair Replace Solenoid. (No pump removal required)

Ford 1.8TD (Delphi Pump)

Fault Lumpy idle usually with grey smoke
Cause Advance Solenoid Failure
Repair Replace advance solenoid. (No pump removal required)

Ford 1.8TD (Delphi DPC Pump)

Faults Erratic idle, Engine spontaneous Acceleration                                                    Cause: Boost diaphragm split causing fuel to leak into the inlet manifold.                                                 Cure: Replace boost diaphragm (Pump removal not required)

Mitsubishi Shogun 2.8 (Zexel Pump)

Fault Starts then cuts out and or runs for 5 minutes then cuts out.
Cause This is due to the pumps drive shaft allowing air to enter the pump (usually after standing overnight).
Repair Replacement of the pumps drive seal is all that is required. (Pump Removal required)

Special note: Do not be tempted to fit a non return valve in this situation as fuel will eventually leak into the engine. 

Nissan Terrano 2.7

Fault Power loss, erratic idle.
Cause Pump spring failure
Repair Pump repair (Pump removal required)

Vauxhall DTI (Bosch VP System)

Fault Difficult to start and/or starts runs momentarily then cuts out
Cause Fuel draining back to tank once the engine is stopped
Repair Injector return seals, also check the return pipes.

Note: Do not be tempted with a fast fix of using a non return valve, fuel will leak into the engine.

Darren 28.05.2020 11:42

Hi , have a Toyota 2ct kit from 1991 2.0 townace, the rectangular top body gasket is leaking , can I replace this in situ maybe !? Cheers Darren

Darell 12.02.2019 20:52

2.4di transit 2002, runs for 1 minute roughly and cuts out

yusupha gibba 03.10.2018 16:05

I have a nissan terrano dt2.7. the pressure of my new lift pump drops every morning. pressurize before starting.

Wayne 12.08.2017 16:04

Hi my van sounds like a train when start it and lacks in power would you say that's the pump spring on a2.4 transit

ads 09.11.2015 11:18

No such thing. PCV are for common rail systems

PAM 09.11.2015 10:36


alex 01.06.2015 20:24

Hi i have a jaguar x type 2.0 d 2005 model it is starting good then after about 3 sec will stops,, never done this before. it could be the crank position sensor

tracy 29.12.2014 21:51

hi have a s reg mitsubishi shogun 2.8 tdi lwb, it has power loss and cuts out? i have fitted a new turbo but it is still the same anyone know what else it could

Craig 24.11.2014 12:13

Hi, Can you send me as much info as possible regarding the rebuild of a bosch cp1 pump as fitted to a Peugeot Boxer 2.0 Hdi 2005.

David Hole 05.09.2014 08:34

Hi 2001 transit 350 TDI starts and ticks over, when accelera pedal is pressed engine cuts out. leave to tick over for 5 mins. engine will rev and drive ok.

Allmakes diesel specioalist 06.09.2014 22:05

Hi Dave,
I am assuming this is only happening on first start up, if this is the case begin by checking all connections from pump to tank are secure.

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