I was wrong on the forward outlet of the fuel pressure regulator as the fuel flows in a back direction though the regulator but it is the forward fitting that you would read the trapped regulated fuel pressure .

Someone recommended from experience that if you replace the failed pump you need to replace the relay as it will be pitted on the contacts and not allow enough current to run a new pump .

Your original relay may be in this condition as you move it around .

 

I disconnected the supply to the fuel rail at the rear of the fuel rail and pointed this into a plastic jug to see the pressure and volume of the supply. I would be interested in a more definite way to actually measure the supplied pressure. I have a fairly complete fuel pressure test kit from harbor freight but it does not have any fitting that would allow me to connect the gauge anywhere near the actual fuel rail on the motor.

I have replaced the relay before but I have spares so I can do so again.

 

Did you change the fuel filter? Even if it is not that, it is part of normal maintenance as I am sure you know.

 

At the rear of the fuel rail is a valid test point and without any numbers on pressure or volume it would be obvious if there wasn't enough as a judgement .

Other then fuel have you verified spark . There is a connector below the washer fluid fill cap that gets corroded like mine called the Papa Indy 1 position 4 ( White / Pink wire ) from fuse # 12 / 10 amp red RH engine fuse box that all coils get there power from as the ECU provides a timed ground . The fuse is shared with more devices ( starter and smog pump relays and air conditioning control module ) and may be getting sucked down . You can pull the smog pump relay but you will need the starter relay , the AC module is hidden behind the glove box surround panel .


There is also a odd fuse location for the fuel pump relay control other then the power half . # 10 / 5 amp RH Heelboard fuse box . This is shared as a power source in the data link connector ( OBD 2 ) . Reference Wiring Schematic figure 21.2 . The control circuit for the fuel pump relay may be sucked down by this device connector and not getting full contact on the power half of the fuel pump relay although there should be a overcenter spring inside the relay . But then you used the direct pump power jumper method I came up with , did you try to start the engine ?

Any questions just ask .

 

Sorry, I had to go on a week long business trip out of town. Then when I got back this week it has been REALLY cold here in NE Ohio. I hope to get back to diagnosing my no start problem later today as it may be a few degrees warmer this afternoon.

I have not been able to get to the fuel filter yet as a result of the above.

Can anyone provide a photo of the special tool required to disconnect the fuel lines from the bottom of the tank?

Also I have the line at the back of the fuel rail disconnected but because of the odd connector there, I am unable to splice in any sort of pressure gauge into the system. Has anyone developed any sort of fuel pressure tap off adapter for the X300 cars?

 

I was not able to find any fittings to install into the lines so I drilled a hole into the forward as installed FPR hex nut area . If it didn't work I would be sacrificing that common item and not the rail . Epoxied a small brass tube from the RC model store and a $ 5 tire gauge . Later will be brazing in a self tapping screw to reseal it . There is a 48 pin connector in the trunk just below the fwd lid opening edge that can migrate off and gives a no start , tywrap secure . No fuse in the security module as it may have been removed during storage will also give a no start . There is a crash / kill switch also to look at , just put a paper clip in the sockets for the 2 white wires

 

See lots of discussions and pictures of suggested tools in this thread "Disconnecting fuel lines".

 

Should be all you need, and more:

https://www.jaguarforums.com/forum/x...quired-163902/

 

Thank you both, Qvhk and aholbto1 for the info.
--
Steve

 

How are you getting on with the fix? Just found a Jaguar TSB 05.1-01 on Quick Fit Connector Release Tool. The said tool is called JD 203, available from Jaguar.service-solutions.com, for US$8.56. There are of course other universal fuel pipe disconnection pliers available in the market, as previously discussed in the link I referenced above.

 

Hello all. The temperatures here in NE Ohio as of last night and today have finally gotten up into the high 20's to mid thirties today so I was able to get over to my unheated garage to do some additional troubleshooting on this issue.

What I did this evening is to unscrew the rear fuel supply line from the fuel rail and temporarily put a fuel pressure gauge at the end of the fuel inlet line. So the gauge was a dead end connection for the fuel flowing from the pump and no follow-on supply to the fuel rail itself. I did this just to see if I did indeed have fuel pressure from the pump.

Once I had the gauge hooked up like this, I removed the fuel pump relay from it's socket in the trunk and jumped 12v to the forward spade terminal connection to run the pump full on. Unfortunately my connection to the incoming fuel supply line for my gauge leaked but the watcher who was eyeballing the gauge for me while I applied the 12v power in the trunk said I had at least 60PSI of pressure indicated on the gauge even with the leak.

As a follow-on test, I removed the gauge from the line and reconnected the fuel supply line to the rear of the fuel rail. Then while I was doing the same jumping of 12v power to the forward spade terminal of the relay socket, I had my helper crank the engine with the key. Same condition, no start with small chuffs once in a while.

I am now thinking my fuel pump diagnosis might be in error. Idon't want to go to all of the effort to remove the tank & fuel pump if that is NOT my problem.

Is it possible I might have a problem with the crank sensor or other ignition part without throwing a code to the OBDII system?

I stated before that when I am cranking the engine, I do see the needle on the tachometer move which I thought someone earlier in this thread indicated my crank position sensor was good. What else should I be looking at?

 

The crank sensor can fail in some of its uses but not all ( tachometer , ignition timing , ECU map data , and fuel pump control )

Did you swap the relay with the rear window defrost ? Static pressure is one thing but pressure and volume is what is truly needed . The 60 PSI could be a good reading . You could have a pitted power contact on the relay not allowing enough current to drive the pump .

It theory the initial 3 - 5 second prime charge can be trapped by the tank check valve and your gauge and may be what you are reading and may hide the fact that the commanded 3rd click of the relay may not be commanded back on by the crank sensor .

 

OK, but if I am manually powering the fuel pump by jumping 12v power the the front spade plug in the relay socket and then cranking the engine with the key, still resulting in the same no start condition, doesn't that seem to indicate it is not the fuel pump?

 

If you find fuel at the engine front then it would not be the pump, but more like ignition issue. Even when the odometer jumps does not necessarily mean that the crank sensor is not faulty. This has been a very long thread; are you sure your battery is strong enough to crank the engine? Extreme weather means the starter needs to work much harder than usual to move the flywheel.

 

Is the car stored outdoors? My 95 XJ6 was used for short drives and stored outdoors for 30-days in below freezing weather. Exhaust got plugged up with ice and car would not start. Thaw it out and drill seep holes in muffler. Please add to X300 checklist

 

When this issue first occurred the car had been in an outdoor parking lot at an airport for a couple of days during the beginning of the east coast cold snap. So exposed to 15°F temperatures. However I had the car towed to my shop where it has since then been stored indoors for three or four weeks now. I have been making sure the battery has a good charge and the engine does turn over just fine on the starter.

With coil on plug style ignition what is the procedure to check for spark? Pull one of the coils, put a spark plug into the end of it and crank the motor while grounding the end of the plug? I think I will try this today to see if I am getting a good spark.

Also just out of curiosity, where is the fuel filter located on this car? I know on the XJ40 cars the fuel filter was under the car just in front of the left rear wheel. Is it in the same location on the X300 cars? Mayb I can figure out how to hook my fuel pressure gauge into the system at the fuel filter connections.

 

Yes on the filter location , spark testing procedure , jumping of the fuel pump power procedure . Look for the condition of the Papa Indy 1 connector pin 4 with the White / Pink wire as this is the power source for all spark plugs . For spark plugs power ( not control ) fuse # 12 / 10 amp Right Engine Fuse Box . For injector power it comes out of the ECM Controlled relay # 5 located behind the right headlight fuses # 5 / 5 amp and # 11 / 20 amp Right Engine Fuse box . You can feel for the relay to click and swap with the Fog Lights relay . Although you may get the commanded click of the relay doesn't mean the power contacts are not bad .

Hope this gets you further along in your resolution . Any questions , just ask

One thing to consider is the Fuel Pressure Regulator may be ruptured ( cold related ) and bypassing all that fuel back to the pump leaving little for the fuel injectors . You mentioned a sometimes puff . To test the pressure regulator you would have to test with a T fitting and not have the regulator and return line remove from the test configuration . I did this by drilling a hole in the regulator hex nut area at the Fwd point as installed . Have out checked for the vacuum line on the regulator ?

 

Sorry, for being so dense but I have read through the previous replies to this thread and maybe I am missing something but where is this "Papa Indy 1 connector" located at exactly?

Second question, if the inertia switch was tripped would powering the fuel pump by jumping 12v to the front terminal plug in the FP relay socket bypass the action of the inertia switch? I.E. does the inertia switch just disconnect the fuel pump from pressurizing the the fuel system or does it also have something to do with the ignition system or the actuation of the fuel injectors?

 

Also where is the inertia switch located on a 1997 XJ6?

 

On the right passenger right foot area fwd of the ECU . From what I have read they don't always reset . You can put a paper clip in the connector between the 2 white wires and leave the black one alone .

if the inertia switch was tripped would powering the fuel pump by jumping 12v to the front terminal plug in the FP relay socket bypass the action of the inertia switch? Yes

does the inertia switch just disconnect the fuel pump from pressurizing the the fuel system or does it also have something to do with the ignition system or the actuation of the fuel injectors? Researching , Pin red 36 into the ECU comes from the inertia switch . There is a discrepancy in wire colors somewhere

Editing

Have you removed the ECU connectors and checked for common corrosion ?