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I'm having a hard time finding information on this so I thought I'd get my butt into this forum and ask you guys. I don't quite understand the fuel system on my S-type 2001 3.0 V6. I had my fuel pump module (along with pump) changed a month ago, and discovered that there's sort of a second one on the drivers side as well. Why are there two?
Reason why I'm asking is because after I changed the entire fuel module/pump, the car shows that there is more fuel than it actually is. The other day I discovered that when I'm at 45% fuel and make a sharp right turn, the car temporarily loses acceleration and sometimes even dies on me. Surely it can't be the fuel gauge, but what if the other old one isn't "matching" the other one and maybe the communication between these two somehow fail? Any ideas? When car shows 30% on the dash, then the tank is almost empty.
To help understand.
There is only one electric pump to send fuel to the engine.(right side of 'saddle-tank')
The 'transfer-pump' or jet-pump constantly moves fuel from the left side (no electric pump) to the right side to keep the level full on that side.
The two fuel level senders are set to AVERAGE to two levels on each side of the saddle tank.
.pdf from my training class student guide.
Will take a look at this today and come back. Is there any way to check if it's completely broken? By default I assume the left side of the tank should be full compared to the right one if it's indeed broken?
I had my fuel pump module (along with pump) changed a month ago...
The $64,000 Question:
Why was the pump module replaced? What symptoms were present? I'm just wondering if there may have been some other fault present, in addition to whatever led you to have the pump module replaced. A little history would help.
Do you know if the shop did anything with the module on the left side of the tank? If they didn't touch it, it seems very unlikely it would suddenly act up at the same time as the module on the right.
This thread has some details about how all the components work together:
Here's an excerpt from the training manual, which may have already been posted:
Note the "fuel reservoir" which surrounds the RH pump module. A jet pump on each side of the saddle tank keeps this reservoir filled, to feed the single electric pump. You had mentioned the engine starving for fuel in a sharp corner. That would make me think the reservoir is not being properly refilled, for reasons still unknown. Considering there's a jet pump on each half of the tank to do just that, it would be very helpful to know if the left side was touched at all. If there was something wrong with the new module's jet pump, the reservoir is only being refilled at half speed or less.
The reason why the fuel pump on the RH was changed was because the dealer I bought the car from messed the module up (the tightener caps or whatever they are called, for the fuel lines were broken and fuel was leaking because of that). Also the pump was going bad, as the car died after 20 minutes of driving. So he ordered a new fuel module with pump, and I replaced it myself because the procedure was very simple.
The LH module/fuel sender/whatever, was not touched at all.
I just inspected the LH and that side of the fuel tank is completely full, while the RH is right now half empty.
I just checked the LH module, and I noticed there was some grey/silver goo on the electrical connector so I tried to clean it off with some elctronical cleaner just in case it's doing something.
The second photo; the black and green line is constantly pouring fuel. I took the fuel pump fuse out and cranked the car to release fuel pressure but this one is constantly pouring gasoline. So I can't disconnect it and look at the module properly. Also I noticed that this LH tank is entirely full, while the RH is only half empty (showing about 75% on the dash right now).
Okay one of the fuel lines finally decided to stop squirting gasoline... So I got the entire thing out. So apparently this one HAS been touched by the previous owner/dealer. Seems like he tried to glue back together one of those hoses, because they are now spinning and are not stuck, and there seems to leak fuel from exactly those two white glue poops. Also the filter that was on the module was completely broken. I have a spare one that I will install but is it worth trying to fix the hose with epoxy glue or something?
As Frank Zappa would have said, "Yowza, Yowza, Yowza!"
I'd say you've found the problem. That's the good news. The bad news is you've found the problem. With those hoses sealing so poorly, no doubt the output from the jet pumps was accumulating in the left side, not the right where it belonged. This meant below a certain level of fuel, the electric pump on the right would run dry.
Most likely your fuel gauge was reading properly, so that is one less thing to worry about. Unfortunately, even though the system has two senders and seems to be accurately reporting the total fuel quantity, it is not smart enough to alert you most of that fuel was collecting and staying in the left side where it is unusable.
How to fix the problem? Have the ends of the hose been trimmed back? Hard to tell with all that sealer, but it appears so. I noticed the other hoses have a straight (non-corrugated) section at the end. If the suspect hose has been trimmed back, I doubt you could ever get the corrugated part to seal properly. Are the hose barbs underneath still in good condition? Perhaps you could fabricate a replacement with conventional fuel line?
If no joy with that idea, your next bet would be to replace the entire module. The Jaguar part number is XR858832, item #4 here:
Much to my surprise, I'm seeing the hose (#13) may be available separately as Jaguar part number XR817553. I do NOT know if that is the exact piece you need, but it may be worth investigating.
Another option is finding a serviceable used assembly. eBay? Here's one example, but it's in Europe and shipping is spendy:
So I made a little, something we call here in Sweden "polish solution" (ironically I am polish..) by attaching a PVC hose with clamps to secure the fuel flow. It worked for a few days until one of those hoses flew off again. So I would have to go to some specialist who can professionally seal those hoses and not do what I did lol. But I did check the other side of the tank and they are now perfectly even, which means that the fuel from the left side is evening the tanks out, compared to before where the difference was huge. So at least now the problem is officially confirmed!
Here is a picture of my stunningly amazing solution, which in my opinion deserves a nobel price:
Here is a picture of my stunningly amazing solution, which in my opinion deserves a nobel price:
I'll second the motion!
Maybe try constant tension hose clamps. If the hose material compresses (which is normal), a screw-type hose clamp will lose its grip. A constant tension clamp maintains its grip, as the name implies. Here's one example: