Usually my car doesn't get left for long without being driven, but a couple of times recently it's had a few (only 4 or so) days off, and then been difficult to start afterwards. It occurred to me last night after the second occurrence, that I should perhaps try 'priming' the fuel system to avoid it in the future, but does anyone else have any ideas / explanations?

 

Mmmmmm, mine doesnt seem to care, fires right up, even after 4 weeks.

Suggestions, based on my findings, and not necessarily X300 specific, and in no particular order:

Old spark plugs.

Fuel filter requires renewing.

Battery just NOT quite up to snuff, this is an X300 one, as they are a tad picky about that item.

Fuel pump getting tired, not common, but it does happen.

That black goo is blocking the throttle body, very common.

Injectors need a clean, which I do with a good dose of injector cleaner, on a regular basis.

 

It catches very briefly and then dies, before taking an age to catch again - that pointed me towards a lack of fuel in the lines, hence the thought on priming. I may be way off!

Battery is recent and fine, Spark plugs are new, TB is clean...

Fuel filter is on the to-do list (it's been sat in the boot for ages but for some reason hasn't fitted itself yet), as is injector cleaner now! Cheers

 

HAHAHAHA.

They do a wonderful job in the boot, and add that they dont get dirty, or clogged, bonus motoring.

I never used injector cleaner very regularly, until the X300 and S Type arrived, now it is a regular part of things. Some people get all hissy about them, snake oil and suchlike, but its my car, and I believe it does make some difference, and I buy it bulk from work.

Thinking about the "catches and dies" is a fuel "up to the rail" issue, and I had that with the V12's initially. So I reckon fuel filter is #1, then pump aging, sadly tank out for that sucker.

 

Cheers Fuel filter and fingers crossed, I reckon. There really is a never ending list with this car. I'm trying to avoid spending too much on it at the moment, as I can see it ending up cube-shaped if the MOT brings up yet more bad news! I can just about justify fixing this lot, but not much more...

Current issues include (but are not limited to):
Clunky gear shifts (particularly shifting D to R, and at lockup)
New discs/pads needed all round (it stops ok, but they look 'orrible)
At least one front balljoint
Broken seat mount
Noisy water pump (which has actually gone quiet again)
Suspect rear left wheel bearing... which'll probably turn out to be the diff.

And then minor things like the rusty front wings & boot lid, non working A/C etc!

If I'd spent more on the car, I wouldn't mind spending on upkeep, but there are so many cheap ones out there that there's surely got to be a limit?!

 

I agree with the spending.

We dont have inspections where I call home, so the pressure is not on every year or so.

The trans is more than likely fluid related, a simple drain and refill (undo the filler tube big nut and let it run out), does absolute wonders for the 4HP22 in these. Normal ATF is cheap.

Rear wheel bearings, LHR on RHD models is the most common.

The rest is not too expensive and mostly DIY, and shop the aftermarket for bits, I do.

The other cheapies out there are possibly in the same condition ae yours, so a bit of the "devil you know versus the one you dont" comes into play here.

Rust, we dont have it, lucky, hell yes.

 

It's not all bad - honest! I've only had it 6 months, and the 'done' list is twice the length of the 'to do'... both lists keep getting longer though!

I'll give the trans fluid a go - it looks nice and clean so I was leaning more towards ****ed mounts somewhere or just imminent catastrophic failure...
Also need to adjust the cable - everything else I've looked at has needed attention so I'm sure that will too. Can you recommend a fluid/spec? I know nowt about this auto malarky!

 

Driving home this evening, it occurred to me that the clunks appear (/become noticeable) once the car's warmed up. Your suggestion on the fluid must be looking more likely to be the fault?

 

OK, the fact is more noticed as it gets warmer is fluid.

That kickdown/change cable adjustment also has a marked effect on gear change, NOT the in and out of D or R. The general cause of that "take up" clunk is high idle, worn mounts etc.

The trans calls for good old standard Dexron3 ATF, and that changed annually is sweet. I run Synthetic ATF in all my Jags, coz I can, and it is just that much sweeter, but it also costs more, lasts longer, handles heat better. Down here we have ATF that is specified as "Multi vehicle Full Synthetic ATF", and is a direct replacement for Dex3 and many other fluids.

 

Regarding the original question... I am not a jag specialist, but back in the BMW days, the first thing I would look for, is the one way valve that keeps the gas from running back into the tank. Could be installed on the pump itself, or right after, on these cars, but surely someone knows more about that.

 

Of course, it wouldn't help if the bolts between the transmission and the propshaft were loose, would it?

Adjusting the cable (to get to the shift points in the jag tech manual) has also helped, but it's not quite where I want it to be yet. I reckon a change to synthetic ATF is on the cards... I'll get it in bulk so I can do a few changes - get as much of the old stuff out as I can.

 

Good shout - does anyone know if such a thing is installed? I've given the fittings on the filter a good soaking, but it's not keen to come off yet!

 

OK, I'm no expert but I'm seeing a pattern here.
It seems to me that when you look for a problem in a specific area, you find it.
My solution? ..... STOP LOOKING.
Works for me. I haven't found a fault for years. (Insert smillie face)

 

Gut feeling, and that is all it is.

Being an "in tank" pump, I dont believe there is such a valve. If there is, it would be in the pump itself, and that is a Nippon Denso pump, same as Toyota, Mazda etc.

You will need to soak those filter fittings real well, and get yourself the 2 o/rings that are inside those fittings, coz they are maybe buggered also.

 

Grant,
Back in January in this thread you said you're using injector cleaner .. as well as the 2-stroke outboard oil?
Which injector cleaner do you use - Wynn's? What is best?

 

Al,

I use whatever is on special, even bulk buy sometimes. All the same brew, just paying silly $ for the name mostly.

Never used outboard oil some hve however, but I am a tad concerned about teh catalytic $ if what you put in the tank is not cat friendly.

I also ONLY run our 98 octane fuel in them all, even the lawnmower, coz I knick it out of the X300, mm.

Never ever get ethanol laced fuel, luckily it is very hard to find in my bit of our island.

 

I agree with Grant. If it exists, it's likely incorporated in the pump itself. Nothing in the manuals or parts catalog sugegstes a stand-alone anti-drainback valve.

I'll just add that, in my experience, a healthy fuel pump will re-pressureize the fuel lines in just a couple of seconds so, if drainback is coccuring, it shouldn't cause very much of a delay in engine starting at all.

A fuel pressure gauge would be useful for confirming any problems in this area.

Cheers
DD

 

Hah! I think you may be onto something there; I'm a fussy so-and-so. It's fairly standard for me to find something 'wrong' with any car that I drive - usually something that the owner has been ignoring / not noticing for months/years...

 

Thanks again all - I really do need to get the filter changed and then I'll report back.

It could well be something to do with the fact that it runs on LPG 99% of the time - that's certainly the reason I've not prioritised it more highly anyway!

 

There ya go, LPG and Jags, not my favourite mix, but ya got to do what ya got to do.

I use LPG for cremating things to eat.

I know petrol is far too expensive, and we are now at $1.70/ltr, but I still stay away from LPG, which is now 0.71/ltr anyway.