You have a air leak problem somewhere between the injection pump and the tank! The injection pump sucks the fuel from the tank, through all the fittings and hoses, and then through the filter head/fuel filter to the pump to become high pressure fuel in the fuel rail for injection. Your injection pump is getting air sucked into the fuel somewhere along the circuit and you have just got to try and find out where! The injection pump will not function properly if there is
any air in the fuel coming to the suction side of the Bosch pump.
You must find out where that air is coming from!
Changing to a second generation fuel head would be a good start as there were leak problems with the one that came on the CRD's originally. Some of us on this forum have installed an in-tank lift pump to insure a positive feed pressure to the Bosch injection pump at all times... You can do a search on in-tank lift pumps on this forum if your are interested?
Good luck and keep posted as to the outcome....
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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