I've got an idea what's causing the problem and I'm going to be researching it as soon as I finish with this post but figured it was worth confirming or getting other opinions. Wife drives 2001 XJ8 daily to work and back, gets home yesterday asks what Beer I'd like her to get and heads off to the grocery store. 30 minutes later she's calling saying car won't start. Symptoms - Give it a min to set and turn it over and it fires and stutters like mad for 10 seconds and dies. Try it again and it fires, stutters and dies in 5 seconds until it just stutter fires. Let it set a min or 2 and I can start the process all over. Threw a reader on it and no codes. Get it towed home and same thing - (basically acts like it's out of gas). Now the interesting part - walk out first thing this morning and she fires up like nobody's business, runs without a hiccup, and has started without incident every time I've tested it today. Still no CEL or codes being read.

 

What is the status of the secondary tensioners?

 

Entire Timing system, chains, tensioners, and front cover replaced about 3 years ago. Upgraded to aluminum parts for thermostat with a new crossover. Replaced the new water pump installed along with it about 2 months ago due to bad shaft seal.

 

Jim, a little more info. When I replaced the water pump a few months ago, I made the mistake of getting knock sensor connectors wet when I tried to clean off the spillage. I'd had no issues up to the swap with knock sensors but for a week or so after I was pulling a consistent knock sensor code. I had the stethoscope out trying to figure out what it was and could hear nothing but a clean whirrr under the cover. Finally had to pull both sensors, clean connections on both ends and the codes disappeared. Car has been running clean up until last night and fired right up about 20 minutes ago and ran smooth. I could hear fuel pump clearly last night and today, I'm thinking it's a fuel filter issue, got some trash and over night it either dissolved or backed out.

 

Sounds like your wife bought the wrong beer

 

Nah. It was the lack of cat treats with the beer.

I vote fuel system, but since you can clearly hear the pump, then the fuel filter is an easier job. It takes the same fuel filter as the Yukon. BTW, the parts kid tried to tell me that the reason they didn't have the filter in stock was that it was probably not a popular number. Then I told him the number was for most GM utilities and pickups.

Did you get a load of gas recently?

 

To be clear, can you hear the fuel pump when it doesn't start? You can also try depressing the Schraeder valve on the engine and see if fuel comes out.

 

No it's setting at almost half a tank. Been checking it all day and it has fired up as fast as I can turn the key. No stutter, no codes, no hesitation, just clean start and clean running.

 

Yes, fuel pump primed up every time, start or no start. Car has been setting for 2 days now in the drive and damn near starts before I get the key in the ignition. I can throttle up and no hesitation, clean on the uptick and clean drop when I let off. I'm going to take it for a run around the block a few times and see how she does. Only thing I've done to it was swap the fuel pump relay (when it wouldn't start) and it didn't make a difference. I put original back in place before the tow and it still didn't start the night I got it home so pretty sure that's not it. I'm going to run a good fuel treatment through it and see what happens.

 

I think I've identified the issue. See if this makes as much sense to you guys. I decide to run a bottle of Sea Foam through before I get into a fuel filter swap. I pop the fuel cover and notice a scum ring around the liner. I pour some water in to see if the overflow is clogged and water pools about half an inch. liner has split around the overflow tube and nipple is setting up high. The light flickers so I pop the fuel cap and I've got water getting past the cap gasket. I made up a duplicate and doubled the gasket and I'm getting a good seal now. We've been relatively dry all summer, but afternoon of the no start we got one of the best rains we've had in months. I'd also bet a recurring but non-consistent knock sensor code I've been trying to ID all summer coincides with the few storms we managed to get this summer.

 

Thought I had this issue whipped, but car is now sitting in a Walgreens parking lot and won't start. I've been starting the car all weekend at random intervals and had no problems. I tried start, shut down, restart. sometimes 4-5 times - sometimes I started it and let it just run for a while and shut it down - other times I'd just go out and start it up then shut it down. Never had an issue. Wife drove it to work today, had to make a run mid-day, then back to work. She gets in this evening to come home, is in Walgreens for 10 min, and car won't start when she comes back out. Right now I'm just letting it set for a couple hours, hopefully it'll start so I can get it back to the house and save me the tow fee this time. When it's running, car runs fine, wife even said it seemed smoother today. Too much traffic and noise to tell if the fuel pump was priming but dealing with same issue, starts and just stutters- before it would shut down, tonight it just stutters like it's about to run out of gas. Really perplexed

 

Why do they always screw up when the wife is driving? I hate that.

 

the very reason I don't let my wife drive mine - you have to be able to diagnose Jag sounds.

 

Bought the car for her, so kind of hard not to let her drive it. She said that it ''ran really well" and it's been clean for me so probably no real sounds to diagnose. Last week she drove about 6 miles home, it set for 20 min was driven about 6 blocks to a convenience store and wouldn't start. This time she drove about 6 miles and stopped before coming home and it wouldn't start when she comes out. Both times car has been run and left setting for maybe 5-10 min tops but won't start. Tried to listen for fuel pump last night but area was too noisy to confirm but with ear to back seat I'm not hearing anything. Would a pump have an issue that caused intermittent failures? I've had to replace others in the past and it was usually an issue of it failing outright.

 

This sounds like a 'leave it with a tech for a few days job' over here. Intermittent fuel pump sounds the most likely, have you ever encountered fuel wash? A throttle calibration update from Jaguar sorted this. I remember a tip from another member on here was to tape a fuel pressure gauge to the window so it could be monitored.

 

It's a failing fuel pump

 

"It's a failing fuel pump" . . . if not a blocked fuel filter. Used to be a common problem in two and four barrel Rochester carbs with their tiny fuel filters which would fill up with dirt then wash clear while it sat with gas backed up . . .

And with our cars, if the fuel filter is dirty, the pump strains harder and then fails, too.

 

First I would look into that :-)

If not that I would suspect some rusty electrical connection. Those are pain to find. I would unplug every engine-related connector, spray with contact cleaner, connect/disconnect few times before connecting back, and hope for the best.

Checking fuel filter/pump as others suggested is a very good idea. ( had this problem on my other car, usually I could hear pump for few seconds after turning ignition on. with clogged filter it was taking noticeably longer ).

 

I know when my fuel pump was failing I would here a whine at start up for like 3 seconds. If you encountered that, then it eventually gave up

 

+1 I agree. My XJR stuttered in a similar fashion a few times before the pumps (mine has two) finally failed for good.

When we replaced them we found the wiring harness going to the pumps was fried too.

Vector