Need help, I have a "Fuelling Failure" notice. The car occasionally will not start until I disconnect the fuel delivery pipe after the vibration damper, and have someone activate starter, while it fills can of fuel. Once I reconnect the fuel delivery pipe, car will start until the next time. I have checked the fuel pressure and its to spec, once thing happens is one of the checks,says "turn on ignition, but don't start car" pressure should be 20lbs, it does start at 20 lbs but decreases on the guage to zero.

Would sure appreciate some technical expertise on this, thank you.
Ken Horn

Submitted by khorn49@att.net on Sun, 11/14/2010 - 19:45

Found out what "Fuelinbg Failure #3 " It is the sensor on top of the water manifold, (just above the Fan) Repalced this, and boy does the car run great, I am sure the new fuel pump helps! Thanks for all help fellas.
Ken Horn

Submitted by bonnettoboot@e… on Sat, 11/06/2010 - 11:26

Ken you have to focus on the pressure issue first. The system should hold close to running pressure when it isn't running. If it leaks of instantly then there is a problem. Other than external leaks, there are three causes for lack of pressure retention, It is leaking back through the pump one way valve (your new pump would have resolved that). Leaking through the pressure regulator and back to the tank, or leaking into the engine via an injector/injectors. The simplest check is to pressurise the system, then clamp off the return line after the regulator (have someone help you) when the line is blocked the pressure will rise very quickly, so be prepared to release the clamp or switch off the engine.

Submitted by khorn49@att.net on Fri, 11/05/2010 - 22:47

Dear William Friday Nov 5th-2010

Pressure drop once engine was tunred off. I replaced the fuel pump today, and car started great, but still recieved "Fueling Failure" on the dash.. When I went to restart car about half hour later, no luck, it just turned over with the starter. I am begining to wonder if its the "ECU" tomorrow I am going to take off the crankshaft position sensor. We have great scrap yards about 80 miles from me in North Hollywood, they have this week about a dozen Jags of the same type. Think I will replace the current "Crankshaft sensor"

Any ideas you can help with is appreciated , thanks for your past help.
Ken Horn

Submitted by SE98-32482CJ on Wed, 10/27/2010 - 13:16

Ken the fuel pump only holds pressure when running--there is a pressure regulator that should hold it at the fuel rail. Sounds like a bad pump or possibly a clogged filter!

Submitted by khorn49@att.net on Wed, 10/27/2010 - 11:29

This is Ken Horn.

Sorry I have 1988 Vanden Plas Saloon, I have thought about this problem for the last few days. Is the non starting due to the loss of the 20lbs pressure, which is when you just turn the ignition key on. Would this be leaking injectors, or the fuel pump just not holding the pressure.

Thanks for all your help.
ken

Submitted by bonnettoboot@e… on Mon, 10/25/2010 - 23:09

I wonder what happened to my post? It said; I have never heard of the 20lb secondary pressure. You either have a weak pump or some kind of restriction in the system.