just bought from elderly guy--2001 Stype 4.0 jag with 19K miles. has 600miles in last 2 1/2 yrs.--wifes car-she died 3 mos ago and old man is blind.--son drove it a"few" times to the PO. they had been running 87oct last 600miles as per "experts advise". i have added 1/2 tank of good gas and a 1/2 can of sentry and trying to run out old gas and fill with new 93oct fuel asap.-----easing up throught he gears it is OK until it reaches final high gear--when it drops into this gear, under light to moderate accelleration it stumbles ---as you continue to higher speeds it appears to smooth out. i can set cruise on 60--70--80 and it runs along apparrently smooth as silk---at idle ,it will be smooth for 30secs or so and then it appears to skip intermittently from then on-------------I am a novice and far from a jag dealer-----(central florida)-----HELP!! TIA---doug bkrdoug@yahoo.com FIXED---#4 coil !!!!! thx everyone!! doug

 

My first thought, given the static life of the car prior to your goodself, would be a partially clogged injector. These can be intermittent.
The first and cheapest remedy would be a bottle of "Forte" petrol injector cleaner in the petrol tank when only a couple of gallons or so in the tank. You have I would guess a 50/50 chance of curing it, but it might take a few miles of driving. Add petrol in one gallon amounts as you use it until it becomes clear whether you have a fix or not.
If unsuccessful, next would be removing the injectors and having them professionally cleaned, look for an ultrasonic-cleaner equipped workshop for this.
I wouldn't put too much score on an errorcode here, they are often just simply wrong.
I had the same prob. on my XJ6 as I hardly used the petrol, because LPG gas was fitted, and it's half the price of petrol here. I could even start it on gas, which was the root cause of my clogged injectors. There is something in petrol that clogs the injectors if they aren't used regularly.
Leedsman.

 

My second thought would be a minute air leak somewhere in the air induction to the engine. Convoluted rubber hoses are a common leak, but it could be anywhere. A careful visual examination is good and if you can catch it while faulty at idle you may be able to hear the slight "hiss" with a rubber tube in your ear, the other end being placed in likely spots for a leak -- similar to the way they used to match up twin carburetors with a stereo stethoscope, listening to the intake roar around the throttle butterfly.
If none of this works, you are going to have to get serious; there are many experienced people here who will help.
Leedsman.

 

Sounds like 'on-plug-coils' starting to fail. Pull a plastic cover from the coils and if they are green/yellow labeled coils you should replace all of them with the newer ones. They can be purchased for a Lincoln LS 3.9 rather than the 4.0 Jaguar dealer coils to save some money. I had a 2001 4.0 S-Type and replaced all mine with the newer (at the time) Black labeled coils. I have a box of 30 or 40 old green/yellow label 4.0 coils from my days at the dealer. Some are probably still good but it is not worth the time to install and remove them to see if they will work. I kept them for the Parts Guy who was always losing the warranty parts for return so he kept 'looting' my stash.

bob gauff

 

thanks guys--------------------BOB i am going to burn this tamnk of old gas and then burn a fresh one with sentry (a great cleaner used by the marine industry)---my sons are both mechanics . am thinking if i go that far i will put in new coils--wires and plugs.---sound reasonable???---if that dont handle it and the clean fuel dont--will have injectors looked at. leedsman: i am 78yo with BAD ears!!!!!! thanks very much guys---doug

 

With 19K miles I don't think you will need spark plugs unless they are FOULED. There are no wires because you have ON-PLUG-COILS. The coil and wire are in one package. They were a constant problem until the later ones introduced.

bob gauff

 

MOTORCARMAN-----BOB--thank you very much . that info really helps me.---what a great thing to have pros like you to help old dummies like me! doug

 

I also live in central Florida. If you do need a mechanic in the end, Jaguar Orlando is seriously overpriced for service. I recommend that you go to All Jaguar, it is off the Ronald Reagan pkway, near Sr 434. In longwood, near the bentley dealers.

They are the mechanics my family use for our 2 jags... Very good prices. Excellent service. They are great at all Jaguar. (If you do end up needing servicing, or a headliner, anything else, etc)...
Nice S-Type, by the say. The 4l is an excellent engine.

 

thanks IAN -----someone else on the list said they were good---got them bookmarked.------MY son has a shop where he builds ground up and any phase builds and restorations for real high end rollers(built twin engine harley bike and the "DEADWOOD" bike (won every trophy from daytoa to sturgis and has traveled the world on display---he also does the work for a large car dealers "MUSEUM".------anyway he changed the plugs and #4 coil and fixed the problem of stumbling. Mr androukalis has been a big help with his knowledge of this ford,lincoln/jaguar car!! where are you at? i live in crystal river and there are no dealers close---all jag is a long way from here. call crown ,but, they were ignorant of jags and arrogant besides. thanks again doug

 

I'm in Apopka, (Closer to Altamonte Springs, really). I live close to 434 so it's a straight shot to All Jag. Yes, it's true I've gotten a lot of help on this forum. It's super useful, Sean B has been especially helpful, since he has a similar car to mine and he personally rebuilt his from the ground up.

Lots of 'veteran' members who know loads of information. And certified techs who are extremely knowledgeable.

Crystal river is really out there! I always assume "Central Florida" means Orlando area, but there are a lot of smaller cities strung throughout the state.