OK! When you turn the key on the pump will turn on for just a few moment then the power to it is turned off until the car is started then the pump has constant power that is why you have 2 fuses and relay feeding the pump.

I ask about the pressure gauge because you need to know what the pressure is on the rail. Your pressure can change by the pump, fuel filter and last the pressure regulator. You say the car ran fine when the regulator was leaking but now it is not I am wondering if the regulator is now obstructed. Just a note; I recently had the P1316 & P0300 and it was the filter. Go Figure!

You are unable to find or get a loaner pressure gauge?

 

It can't be the filter. I had a new one installed no less that 4k miles ago.

I would be inclined, and perhaps hopeful that the regulator is somehow obstructed.

I don't have a pressure gauge and I don't know anyone that has one. It seems like I will have to walk to the nearest auto parts store and see if they can either lend me one or sell me one.

 

First off I don't believe you can use a tire gauge, so nix that one.
Since the pump is 'running' and supplying fuel keep in mind other components that may cause restriction, have you ever replaced the fuel filter? Your codes are showing issues on one bank, I believe the fuel feed is common to both banks. Replacing the fuel pump in the tank is no easy task, usually they run or not, very rarely will they present partial pressure again filter? Dropping parts is not listed in the JTIS ;-) you wouldn't think there's that much to it but at 250 a pop they must be more complex than they look.

 

Well, thing is, my fuel filter is quite new, I replaced it less than 4k miles ago, and has been working well ever since. I doubt that the filter would just crap out from one day to another.


If I could find an XJ in a junker I could just check if the regulator is really dead.

It was rainy the night I left the car sitting without the regulator, even with the precautionary shop towel and ziplock bag. Maybe some humidity got into the system. Or maybe, some of the shop towel is lodged in there (god I hope not.)

 

What are the symptoms of a failing fuel pump? Maybe it matches anything I've been observing in the past few months.

Here's what I had observed:
Cold starts would take easily anywhere between 5 and 25 seconds while cranking.
Warm starts were usually quick.

At some point, I noticed my car requiring me to step depress the pedal further to get it to pick up the pace or even change gears, even in S mode, specially during highway driving. I used to think the transmission had learned I was driving very passively, but I usually alternate my driving style depending on my mood. So pretty much, within a few hours I could be driving aggressively or passively.
I do have trouble listening to the fuel pump. (Maybe I don't know what to listen for.)

Some of that stuff I thought was a consequence of my cracked intake tube, but I swapped for a new tube, and got a new air filter, a new part load breather hose, and because of ineptitude, I was also forced to get a new full load breather tube. The car did accelerate much better, and harder, however, I still had to depress the pedal more to get a gear shift into a lower gear. (ie from 4-3) Sometimes, under full load, and although, less markedly after I changed the intake tube, the car would accelerate hard when under full throttle, rpms increased, and then suddenly after about a few more revs, the car somehow picked up even more (surged I guess), and revved up faster. That felt like if the car had just gotten boost after turbo lag. The car is however NA. The slow cold starts persisted, but the blowby was cured when I changed the breather hoses, changed the oil and added a can of restore.
My mileage was usually 30 highway/ 16 city, but lately fell to 26 highway, 13 city. (This is from before the regulator leak.)

Any of that sound like signs of a failing fuel pump?

 

it ran fine before the leak. He dropped the regulator. My money is that reg is broke. Sucks that it is so costly. I would contact Jagbits.com and ask them if they can cross ref that part to Ford or Land Rover. They did that for me for some gaskets jag did not even offer yet the Rover place had them. Worth a check. Just email them and say you are looking for this part and ask if they know of a cross ref of it to another car that may be cheaper.

 

Well, it's confirmed, the regulator is toast.

I got decent pressure from the schrader valve today. A strong stream of fuel burst out through it when I put the screwdriver in today.

 

You might be able to find a used regulator.

 

00 2000 Jaguar XK8 Fuel Pressure Regulator - Fuel Injection - Genuine, Standard Motor Products - PartsGeek

one lists for 160.00

 

I ordered one yesterday for $148.95

It should arrive on the 4th. Until then I'll be commuting on a bike. I'm starting to consider cycling as my commute vehicle of choice, now that I have one. It's good exercise and I spend no money on petrol that way.

I'd only be using the car on Thursdays, for groceries, and for visiting the parents, which would mean highway driving.

Is it going to cause any issues now that I'll be using the Jag less? Any advice?

 

these cars like to be DRIVEN. Most anyone here will say the same thing.

 

Alright, consider the following: my commute from my apartment to the university is short enough the car is barely warmed up by the time I have already parked. Also, the university parking lot is a great place to get dinged and scratched.

It takes me almost the same amount of time to get there in my bicycle as on the Jag. Short trips like that are surely not good for the Jag.

I'll still be driving the car every week. My Thursday commute takes me 10 minutes by car because of a lab that is nearly at the next town. I still do nearly two hour trips every weekend to visit my parents. Any grocery shopping, I do over here, as well as trips to the laundromat require me to drive the car. I will still be driving the car every day at 5 am for practice. I am not exposing myself on bike for that.

The car will still be driven regularly, just slightly less so.

Anyone have any tips for preserving the car under those conditions? Maybe I should start a new thread about this.

 

get it out on the HWY and open it up a little time to time.

 

Guys you may have noticed, he lives on Puerto Rico. Not exactly a huge island. I know from living on Maui that folks that live on islands do not nessacerly drive around the island that much. That combined with just not that far between locations adds up to low mileage cars that actualy have extream use do to low speeds, cornering and stop and go traffic.

Even thought my cars get less than 4K each a year I service them on an extream wear schedule, every 4K or 6 months which ever is first.

 

so if he got up to hwy speed he could be in the ocean?

 

This is damn accurate. Let me add: potholes are everywhere. It's like driving on the moon's surface. That is exactly why I have spent the last few months doing a restauration of the suspension components after I finished with the cooling system.

I could, as long as I am not on the highway.

Update on the regulator: USPS is ahead of schedule and my new regulator is to be delivered tomorrow.

 

Got the new regulator, installed it, and now, even on cold starts, the Jag starts with barely any cranking. Problem solved.