I am replacing the fuel pumps on my 2002 XJR. There are 2 pumps. Are they the same part? I have read posts in this forum that says there is a fast pump. When I go to suppliers they say two are requires but do not mention that they are different part numbers. Prices vary from $50 to $150 and over $200 from dealer. Any help would be appreciated.

 

The pumps are the same but the short link harnesses are different and plug into the different connector slots on the EVAP FLANGE. Just use the original link harness with the new pumps and strainers.

bob gauff

 

I'm in the middle of the same job. How much fun was it to get the fuel pipes out of the tank? I had to make my own release tool as the big rubber insulator was offset and did not allow room for the standard tool to engage the release tangs.

I got the Denso pumps as replacements. They have different style connectors than original, so I'm having to splice in the new pigtails. On the original lead lines, there's a small sealed box that the wires pass through. Is this just a sealed connection, or are there some components (capacitors or something) in there that need to be retained? I'm also concerned about the connection to the new pig tail; the instructions call for a simple crimp style connector. Shouldn't this have some sort of protection? Like putting some heat-shrink tubing on it? I researched the shrink tubing a little and found that there's many different types, and that Elastomeric is the only type that specifically states that it is fuel resistant. But, that stuff is hard to find in the small size that would be needed. Polyolefin is the most common, and the information states that it is chemical resistant, but will it hold up when submersed in gasoline (petrol)?

 

Here is some thoughts on fuel pumps my conclusion was that fuel injection corp was the way to go. https://www.jaguarforums.com/forum/x...choices-35780/

 

Since you are in there already, you make a few basic measurements on the link leads to get a clue as to what is in the "black box". If you are using a DVM, try measuring in both directions to catch a diode in the circuit. If it is a resistor, it shouldn't be much. Under 5 ohms for sure because the pump continuity test calls for a maximum of 5 ohms. If the measurement directly across the pump is essentially zero, then the remainder has to be in the black box.

On some other vehicles, the fuel pump power source has a externally mounted resistor to lower the voltage, and hence the pump pressure. A ecm controlled relay is used to bypass the resistor when additional voltage and pressure are required.

 

OK, so leave the little "match boxes" in there and go for the wiring? What about shielding the open connections? I know that gasoline will not explode, and the current by itself will not be a problem; I'm just thinking that if those butt connectors ever come together and the fuel vapors .... I have this thing about not blowin up !!

 

A great big bold hint on what is in the "black box":

https://www.jaguarforums.com/forum/x...37/#post430973

 

Thanks, plums; I responded in the other thread.

 

By the way, should I be so concerned with the electrical connections ????

 

dneider; I checked the Fuel injection Corp webite, and they only list pumps up to 2001. Mine's a 2002. The more that I mess with these Denso pumps, I get a better fit.

Austin, huh? I'll be there for Christmas; daughter lives off of South Slaughter and bro and sis-in-law are down in Wimberley.

 

Do you mean that they fit better as you fit and refit them? Or that more modifcations are resulting in a better fit?

I would be comfortable with butt splicers as long as the sleeve fully covers the splice. It is no different than the plastic connectors top and bottom. They have metal to metal and are covered in plastic. Just a different form factor.

Speaking of Denso, is it part number DENSO 951-0008? Do you have a part number for the sock?

 

The more mods, the better. Some of the tangs around the bottom of the pump do not line up with the rubber insulator, so a little bit of cutting with an X-acto knife. The top is definitely bigger due to the bigger plug, so the top isolator does not fit like the on the OEM pump. I ended up working that isolator in from the top, and got a good mount, only to find the pump creeping up a little so that the bottom isolator wasn't seating properly. So, I put a plastic tie strap around the whole thing. (I'll try to post pictures later today when I get home from work.)

Correct part # for the pump; the socks are OEM (NJB6091AA). Those fit perfectly.

I went down to the hardware store and got some "weatherproof" butt connectors. They have heat-shrink ends to make a seal.

 

Lots to like about Austin and the surrounding area.

 

Thanks for the update. The pictures will come in handy.

The secondary has now quit after being forced to do double duty with a dead primary after only two trips of 10 miles.

The measurements make the links highly suspect. The shop has not opened it up yet. But, has agreed to fabricate leads omitting the black suspected suppressor.

The measurement across the system on the primary pump was 1850 ohms, and this morning 2500 ohms. The secondary started at 0.3 ohms when working, measured at 2.3 ohms when the tow truck got involved. 10 ohms or under is supposed to be ok. But, no start. This morning, it read like a capacitor. 20M ohms then 30M ohms then infinity. Repeat the measurement, same pattern of rising resistance to infinity.

Did you notice on the Fuel Injection Corp site that they say "we are rebuilders of ..."?

The opinion of the shop owner and some forums is that Walbro pumps have become unreliable in the last couple of years. This coincides with the sale to another company.

He is happy with Denso, less so with Bosch.

Are you aware of:

Denso 950-0183 Fuel Pump | Frugal Mechanic

Denso 950-0183

1995-2000 Jaguar Vanden Plas
1995-1996 Jaguar XJ12
1995-1997 Jaguar XJ6
1998-1999 Jaguar XJ8
1995-1999 Jaguar XJR
1995-1996 Jaguar XJS
1997-1999 Jaguar XK8

It has a much smaller list of applications than the Denso 951-0008 which leads to the suspicion it would fit better than a "universal" kit. Especially since all the listed applications are Jaguar.

 

I just got off the phone with a tech rep at Denso. I gave him the part number and he said that it doesn't match for an '02 XJR, only for '95 through '99. While I was on hold, I searched the Denso site for a 2002 Jag XJR fuel pump, and it came back with "no results." The same thing happenned on the Fuel Injection Corp. website; no match. I've read in other posts here in the forum that Jag upgraded the pump(s) in '02 (?) I'm doing some more investigation now ...

 

Looks like cars up to 99' had part number JLM20529 pumps, the 01' pumps are JLM20756.

 

I talked to Gaudin Jaguar today, and they gave me another number: C2N 3866. They said that this number supercedes the JLM number.

So, I decided to give up on the Densos as I really don't like the way that they fit. The female connector is much larger than the one on the OEM pump which causes the top rubber isolator to not fit properly in the bracket. I had to put a tie-down strap around the pump/bracket to keep the pump in place. That may hold up, but with all of the work involved, i want this to be perfect before putting the tank back in there. Plus the wiring issue still has me concerened.

I would post the pictures that I promised, but I need some lessons on how to insert images. When I click the icon, it wants a URL, and I have no idea what mine is or where to find it.

 

OK, so the thumb nails came up, interesting ...

Here's one more picture of the top of the Denso pump. You can see that the top isolator sits further down on the OEM pump. The two isolators compress in the bracket holding the pump in. With the Denso, the isolator will not fit in the hole, therefore, the strap to hold it in.

 

What do the isolators look like?(NM, figured it out looking at the pictures more)

And what gauge wiring is used in the link wires?

A larger connector is not in and of itself a bad thing. In addition to the effects of the "black box", pictures of the wiring suggest that is undersized in comparison to what is accepted as being adequate for 10 amps. Do not forget that for the primary pump, while not always at max, will be at least present at all times that the engine is running.

The JTIS troubleshooting section says: "current between 2.5 and 9 A" for the pump current draw test as a pass.

 

Followup question:

What is the diameter of the stock fuel pump body?