hi there im at a loss at the mo,let me explain,,i have a friend whos jeep as running fine,then all of a sudden wouldnt start,i checked fuel rail and no pressure,,diagnosed possible fuel pump and towed it home,,i then replaced the fuel pump,,a little modifying had to be done to get the ne pump into the old pump holder,but this went well and in it ent back in,,i then changed the filter/fuel regulator and proceeded to try and start,,again no start,,well after lots of reading and research i pressumed it must be crank sensor as when tested for spark there as none,,bought a new sensor and fitted it wich was a pain!!!upon testing the car will fire and run very lumpy,,oh no i thought the sensor was bad,,but sray a little easy start and it runs fine wich rules that out,,,been a mechanic for 20 yrs plus and i dont need a fuel tester for me to see the pressure is low,it also dosent hold pressure,,any idea guys as im at a loss any help oukd be muchly appreciated!!!!!!!!!!!!!!!

 

sorry forgot the vital info-2001 jeep grand cherokee 4.0litre petrol,,

 

also another strange thing is when i plug engine tester in and try to probe for codes the digital display goes haywire,,,,but as i said it runs fine if im spraying easy start into it so it must be fuel related,,,,thanks

 

holding fuel [pressure is only necessary when trying to start it when its running there will be 55 at the rail. So either 1 of two things then Because u say u dont have enough pressure and wont use a fuel pressure tester to confirm U have either a ****ty pump or a clog or bend in the fuel line.

 

hi m8,decided to buy another filter/regulator in case the one was faulty,,,really weird if idisconnect fuel pipe from filter and hold finger over it it gets blown off with pressure,but when plugged into filter pressure dissapears,,,this is a upgraded pump i fitted,,as wondering if to powerfull maybe?shutting regulator off poss,,or am i poss losing pressure internall of the tank?tried old pump with water and old filter and pressure is good,,cheers

 

get factory stuff