I've googled and searched these forums for a diagram for the fuel lines on my 99 XJR. I haven't had an luck.

I had a shop replace both fuel pumps, and the car hasn't been the same since I got it back. I smell fuel from time to time, my fuel mileage has dropped from 25 MPG to 18 MPG, and the car falls flat on its face under WOT. If I floor it, let off the gas, floor it again, and repeat a time or two, it will clear right up, and about break my neck.

I have just discovered this U-shaped BLACK NYLON fuel line, to the left of the fuel tank. It is kinked by the quick connect on the bottom, and the other side (the top side) is not hooked to anything. I know it's not the fuel drain tube, as I have located that. Where does it go?

My car ran perfect before the fuel pumps went out, so I know the problem has to be in the replacement of the pumps.

Any help would be GREATLY appreciated!

 

I suspect you have two different problems- I am having a hard time getting a perspective on your photos, but I think you are showing the vent in the trunk. That would be where you are getting the odor!. As to the dodgy performance, I suspect you have something wrong with the second fuel pump or it's electrical supply. I recommend checking the fuel pressure under WOT with a test gauge, with an extended hose, taped to the outside of the windscreen.

 

For perspective, the photo is on the left side of the tank. The top of the line (which is the side that is not hooked to anything) sits next to the line that runs from the fuel pump module back to the tank.

I don't think electrical is the issue, as the PO spent $600 at the dealer to have the wiring fixed when it went out on him last year. The wires all look good, as do the connectors.

It has to be something that the shop did. Something wasn't hooked up properly. They didn't even put the fuel tank back in properly, which is causing the fuel cap to interfere with the fuel door properly closing.

I don't think it's the second fuel pump, as I have read that pump 2 primes the system, then switches to pump 1, with pump 2 kicking in under WOT. Pump 2 seems to be working just fine. Lots of fuel pressure when the key is cycled.

 

Well, you say WOT is a problem- If it is fuel related, then lack of the second pump would be a valid concern. It is easy enough to test.

 

I had both fuel pumps replaced. I provided the pumps, myself. I'm convinced they didn't hook something back up properly. I think the lack of power under WOT is due to air getting in the system, or a vacuum leak. I only smell fuel on warmer days, which leads me to believe the odor is fuel vapor. Plus, my fuel economy has seriously dropped, as if I'm getting too much fuel. Before fuel pump #1 went bad, the car ran perfectly. I had both fuel pumps replaced, even though #1 was the only bad one. I really need to verify that the lines were installed correctly. Also, I saw a post by Plums, where he mentioned a repair shop failed to hook up lines to a canister after replacing his fuel pumps.

Plus, after the replacement for pump #1 went bad as I backed my car out of the mechanic's shop, and he had to do the entire job again, he made sure to test both pumps to make sure they weren't faulty (so he wouldn't have to do it a third time, lol).

 

OK, then your fuel pumps are fine if you say so, but their 1/4 inch long intake pipe with a screen is the only place they can pull in air and it is submerged in gasoline? I will guarantee you that no air is sucked into the 40 psi pipes connecting the fuel pumps to the engine. The tank COULD have a vacuum of -14psi, BUT if it did, it would collapse and the pumps would probably overcome the vacuum anyway. And your broken hose almost assures no vacuum in the tank anyway.
So, you clearly want plums to tell you about his canister and he probably will, but your logic so far is faulty.

The tank emission controls could throw a code and that might just put the car in RP, but you have not mentioned any CEL, so I assume there is none.

I am sure you will figure it out.

 

I know I don't have the experience with Jaguars that you do, but I'm trying to figure this out. Maybe it's getting air in the line, maybe it's not. I don't know. I'm really not trying to start an argument, but something was not hooked back up correctly. Had I not just had everything replaced, it would be logical to suspect the fuel pumps. I don't have a pressure tester, or I would run the test you suggested, even though I'm positive that the pumps are good.

Why am I smelling fuel in the car? The shop had to repair lines that broke during the fuel pump replacement. I've checked those, and they're not leaking. I really need a diagram to make sure everything is hooked up properly. I never smelled fuel before the pumps were replaced. I never had a lack of power before the pumps were replaced. The problem lies in the repair, I just know it. The mechanic who worked on it is an honest guy, and a good technician, but he's never worked on a Jaguar before. This isn't an attack on repair shops, by any means.

Does anybody know where I can find a diagram for the fuel lines?

 

First, "it can't be" and "I'm positive" are bad signs during diagnostics. It means someone is presuming something. The only valid words are "I know".

Diagrams of the evap system can be found in JTIS under the description part of the fuel system sections. Diagrams with a different viewpoint are also shown in JEPC.

Since the vapour pipe is a hardline, that can't be it.

The hose *could* be the drain hose that runs from the fuel filler cup to the underbody. That would not cause any codes but it would let water into the trunk. An open evap system would throw a P0455 and a "check gas cap" message.

On a 1999 you may have the older style tank with a fuel level sender flange on the side of the tank. If so, it is possible to wait until the tank is almost empty and open the flange to do an inspection.

If you used AIRTEX brand pumps ... they have a design flaw in that the outlet nipple is actually an insert that sometimes gets pulled off with the rubber shipping cap without getting noticed by the installer.

That can contribute to a problem with the hoses. They have been known to come off the pump and then some or all of the fuel is being pumped right back into the tank without going anywhere.

The pumps can be jumpered individually at the relay terminals for a listen. I keep a jumper in the car for this use and emergencies where I want to run from the pump I choose. It is a 6 inch piece of wire with flag terminals on the ends that fit into the relay terminals. Do not turn on the key if you remove the relays or the ECU will throw a relay malfunction code and put the car into restricted performance mode until it clears.

If your gas mileage has really taken a dump, you might even suspect that the relays have been jumpered to run both pumps at all times to mask some kind of problem encountered during the repair. With both pumps running, the system will prime just fine even if the secondary is hosed.

The secondary pump is only supposed to come on to prime the system at start, and at 3500 rpm. If it does not come on at WOT, then pinging is the first sign that the secondary is toast.

A fuel pressure gauge can sometimes be borrowed from places like autozone. If not, then they are not terribly expensive. Never run a fuel pressure gauge in the passenger compartment. Taping it to the windshield is fine. The garage performing the repair might be a good place to borrow one since they would want to prove that it is not their fault for the third time.

If the fuel tank is not properly positioned and secured, then that should be attended to as soon as the tank is at a lower level to ease manipulating it.

BTW, any time the tank is opened, the fuel filter should be changed to catch any crud loosened during installation. A clogged fuel filter may also be a contributing factor to pump failure to begin with and would quickly kill a replacement pump.

 

Alarm Bells...

Generally the car will not pull past 3,00rpm with pump 2 out, or blocked.
You need to put the tank in correctly and check the job they carried out in the fuel tank.
It has a Jaguar specific link lead and connection to both pumps, non oem parts will have that link lead cut about or butchered to make the non oem's work, I bet it's in there. Crimped spade ends anyone?

 

Factory wiring was replaced last year at the dealer, per PO. This was confirmed upon my inspection while the car was in the shop, and the tank and fuel pumps were out of the car.

The car will pull way past 3000 RPM. It just falls flat on its face when you put the pedal down. If you accelerate with slightly less gusto, it will pull as many RPMs as you want.

 

Thanks for the info. If I can get near a computer that I can download things on (not allowed at work, which is my only computer... lol), I'll know where to look!

I do not have any pinging, just a loss of power. If I let off the gas and floor it again, it usually clears right up.

The nylon hose is not the drain from the fuel filler, as I have identified that as a different hose.

The fuel filter was replaced along with the fuel pumps (which were Onix brand)

The garage will gladly take care of this for me, at no charge. Unfortunately, they are quite busy and take quite some time to repair my vehicles (as they give me a really good price). My wife started taking college courses last week, so I am unable to use her vehicle. I can't leave the Jag there for a week, being that is is currently my only transportation, so I am trying to correct it myself.

But, then again, I DO have a week's vacation to burn up before the end of the year...

 

Chad:
Sorry if I seemed overly snarky, but as Plums pointed out, you should not discount much of anything right now, no matter what has been done to this point.

Anyway, if the fuel pump installation is the problem, the problem is pretty much indicated by the pressure. A fuel pressure gauge costs less that $50 online and the fittings to get it extended where you can see it while driving will cost another $10 or $15 at the auto parts store. The pressure should run about 40 psi over manifold pressure.

After you figure that out, you simply go down the diagnostic tree to find the root cause.

 

Thanks. No offense taken.

As soon as I figure out where this darn hose is supposed to go, I'll have to get the pressure tested.

On a side note, fuel mileage was up a little and I had a lot more power on my drive into work this morning, with outside temperatures in the lower to mid 40's F. I also do not smell fuel on the cooler mornings.

 

is it this one?
Fuel Tank-4.0 Litre-V8-Supercharged-Unleaded - Parts For XJ Series from (V)812317 to (V)F59525 (X308) | Jaguar Classic Parts UK

 

No, but thanks for the diagram.

It comes off a metal line that is visible below the far left end of the fuel tank. It hooks to that line via a quick-connect fitting. It goes straight up, then bends down in an a U shape. This is the end that isn't attached to anything.

 

Update:

On the day before yesterday, I cleaned the MAF sensor and swapped the two wires that attach to the center of the the gas tank (on the side facing the trunk)

Yesterday, performance was much better. Gas mileage was up to 23 MPG yesterday afternoon, and the car did not bog down once. There is an occasional brief hesitation when you floor it, but it is much improved over how it had been running.

I did smell fuel when I got in the car yesterday, before I even put the key in the ignition. Is it possible I'm still smelling fuel that could have been spilled in the trunk during the repair, even though it has now been over a month since it was repaired?

This morning, it continued to run very well. However, the amber light came on, with the Engine Failsafe Mode warning. The car still has gobs of power, so I'm not sure what that's about. I'll get the codes read later, and will post the results.

 

A better idea would be to clear the codes first.

If you read an old code from before the wire swap you'll be chasing a non-existent condition.

 

The only codes I had before the wire swap were the EGR and transmission range sensor codes. Sorry, but I forget the numbers, lol. I've always had the EGR code. The transmission code is caused by shifting into reverse when the idle is too high (I still haven't gotten around to adjusting the shifter cable, which is definitely out of adjustment).

I've had the car on the road for a month since I got it back from the repair shop. These are the only codes that have presented themselves during that period. We'll see if anything new pops up.

 

Okay, so I just drove the car up to a shop in the town I work in. This is the guy who used to work on the Jag before I bought it. Not the best mechanic, but he is familiar with the car. He found that that hose was broken from the tank. If you look at the picture below, it is located on the side of the tank, just below the number 19 (not the part that #19 is referring to, but the below the number itself)



Also, the light and message were gone and the only code that pops up is my usual P0400. I'll have to get my scanner back from the pawn shop so I can catch this next time it happens.

Thanks for the help, everyone!

 

Okay, so there is a canister that sits to the left of the fuel tank. The nipple that the hose attaches to had been broken off, flush with the canister. That is the cause of my fuel smell, and also why it was difficult to figure out where the hose went.

I used a 1/4" brass air hose mender for the repair. The nipple was still inside the hose, and the hose mender fit perfectly inside of the broken nipple. It was a tighter fit back into the canister, as I could only get 2 out of the 4 barbs on that side of the hose mender to go into the canister.

I'll give the XJR a few days to air out, and see if the fuel smell goes away. Keeping my fingers crossed!