I own a '95 V12 convertible (that I kept rather than trading it in for my XKR). As a result, the car doesn't get driven and is started occasionally. It hasn't been on the road in the past 8 years and normally starts up with no problem when I reconnect the battery. This weekend however, it wouldn't start.


The engine turns over fine, but when I disconnected one of the fuel rails to the left side bank, there was fuel in the rail but there was no fuel coming out of the fuel line when I turned the engine over. I don't hear the fuel pump prime when I switch the ignition on either.


I took the interior panels off the trunk and popped out the sender (wasn't working) and there was some crusty varnish on the metal sender arm which I cleaned off with a wire brush. The premium gas smells like you'd expect from a car that doesn't get used a lot.


I took a look at the right hand rear wheel arch inside the trunk and there's a sizeable ECU in there however I wasn't able to see the fuel pump relay. I'm leaning towards replacing the fuel pump relay first and then digging the pump out of the tank if that doesn't work.


Does anyone have any suggestions as to how to test the relay before replacing it and also exactly where it is located - the relays on the convertible top pump seem to relate to the convertible top pump and not the fuel pump? Presumably, if I remove the black metal panel that is bolted to the bulkhead of the trunk behind the spare wheel, I will be able to see the fuel pump housing on top of the tank and perhaps pull the electrical connectors to get a volt meter across the spades to see if the regulator is delivering 12 volts with the ignition switch on?


Thanks in advance.


Chris

 

Hi Chris , my xjs is an early model but I would think that the relays would be the same set up in yours , I have testing procedures for testing the relays butt if I was you I would use some jumper leads ( just light ones with alligator clips would do ) straight to your fuel pump directly from your battery to see if it runs , this may save you some time. My xjs was also off the road for a long time and my pump was fubar I would also drain the tank before the syrup goes through the fuel system and messes with your injectors. Got to go the Koala bear is nearly cooked on the barbie .PS will get the relay tests if you need them tomorrow.

 

Power the relay and see if you have continuity on the other side

 

Hi Chris , Sidescrollin is right , test main relay , should be the top one , should have voltage at terminal 86 , check for continuity between terminals 30 and 87 on both relays, should have voltage . Check for voltage at 86 on pump relay .That should be enough for now , see what results you get . Still think check the pump first .

 

Also be aware that 1993 to 1996 V12 6.0 have two fuel pumps each controlled by separate relay.

One pump is on all the time, the second switches on above 2850 rpm

 

Thanks for "chipping" in Paul