Well I finally got the IRS back in after putting in new rotors, rebuilt calipers, oil seals ect... on my 1990 convertible. So I took it out for my first drive after buying it to bed the brakes in and everything was going well. After driving for a while with a big smile on my face I noticed a noise coming from the rear that got louder. I didn't recall hearing it before but I did have the top down this go round. The noise didn't change pitch while driving so I popped the boot open and noticed a loud whining sound from behind the battery. My guess is that it is the fuel pump. The car ran fine so I'm hoping that it's just a clogged fuel filter causing the noise. So I have several questions. Can I just buy an off the shelf filter from Wal-Mart or is this a jag specialty shop order? Part numbers would be helpful. Are there any other filters/screens to check or clean that could be restricting fuel flow to or from the pump? Lastly is there anything else that could be causing this noise that I'm not thinking about.

Thanks,
Dan
1990 XJS V12 convertible Marelli

 

For my '88 XJS V12 the fuel filter was nothing special. I was always able to get one from any neighborhood parts store. I suspect yours uses the same filter. Don't have the PN at hand, sorry.

Not sure about convertibles but the XJS coupes had a fuel "sump tank" under the battery. The sump was supplied by the main tank, and the fuel pump was supplied from the sump tank. Anyhow, the sump tank....if you have one....has a screen that often clogs.

Cheers
DD

 

I similarly had a 'loud whining noise' coming from the trunk. A new fuel filter did not do the trick. The whine didn't go away until I installed a new fuel pump. But I agree that going the cheaper route of cleaning the sump screen / installing a new filter is worth a try first.

 

Well I changed the fuel filter and cleaned the sump screen last night. The pump was noticeably quieter. No more whining noise. I was also happy to see that the sump screen was fairly clean, as it is a good indication of the integrity of my gas tank. Though I'm not sure if having a new filter or just knocking the pump around a bit while I was working on it did the trick.
After changing a few in the tank pumps over the years I can say that I'm impressed with how easy it is to get to fuel pump to change it. Though I can understand after looking at the system why fuel smells in the trunk is a common complaint. I was unable to do the job without spilling some gas.

Thanks for everyone's input!
Dan

1990 XJS V12 convertible Marelli

 

Whining noise usually means that pump is not receiving adequate fuel supply, therefore creating vacuum.

 

my old one made a pretty loud whirring sound. It died after about 6 months. Idk if it was being noisey because it was crapping out or if the OEM one is like that.

replacement was 30 dollars and makes nearly no sound at all.

 

my cars smells like gas forever you are not alone

 

Hello, I had the same issue. I worked hard to find the source of the noise. It turned out to be the check valve (return valve) in the gas tank. It's located right before the fuel pump. It has nothing to do with the operation of the fuel pump. I isolated the return fuel flow from the fuel line after the fuel body under the hood to the gas tank. The car ran without the noise. So, I removed all the hardware holding the tank and pulled the tank back enough to get to the top to remove the cover. I looked inside with a mirror and saw the check valve right before the fuel pump (after replacing the fuel pump with a new one). I cut the rubber hose behind the check valve to disable the check valve. The noise is gone forever! You might try the same. Good luck.

 

Is there a part number for the check valve? What purpose does it serve, if any?

 

Sorry, no part number. I guess it was part of the original gas tank design and they didn't intend to change the part. From my research, the purpose of this check valve is to prevent gas from back flowing in the event of an accident where the incoming gas line has been severed. My opinion, you can add a check valve to the incoming gas line right before the gas tank ( if you believe it's worth the trouble) and achieve the same result. My opinion, disconnect and don't look back. Good luck.