That's called 'the lurch'. Common to many 2003+ S-types irrespective of engine option.

Jaguar S-Type ZF Gearbox Lurch fault

 

Thanks for the information. I'm both disappointed and relieved that it's a common issue. It appears there's no remedy for it which is too bad because it's annoying, and dangerous if you trying to beat something. I wonder if a transmission service or different kind of fluid would help?

 

The remedy is a software patch which cures it in most cases.

 

the sport button seems to get rid of the lurch but does affect fuel consumption . it is a common thing and not necessarily a fault i had an XF which also did the same so not exclusive to the j box just to jags in general my xk8 did the same under some circumstances but it is one of the many foibles of jag and having been instilled with a love for all cars jaguar by my dad and living within a stones throw of coventry the home of jaguar it is just one of the things to be accepted and lived with. It can be overcome with a remap if you want to go to the expense BUT also try a new MAF as they are not expensive and IF they are starting to fail they can cause this issue to be more noticeable even before they cause any fault codes on the car try an obd11 scan to look for po171 & po174 banks too lean just to double check as when you say dangerous it points to a serious delay which is not normal just slight ones generally

 

The common engine swap over here is remove the 4.2 v8 when faulty and fit either the 4.0 v8 or 3.5 v8 neither of which are as good as the 4.2 v8 but are more readily available and therefore cheaper but even then the adaption of the electronics takes some doing and is never straight forward

 

I hit the sport button by accident once and was trying to figure out why it was revving higher on the highway.

I said dangerous because I was at an intersection once, trying to cross a main road, and gunned it to beat an oncoming car and get across. It didn't "gun" very well and the delay left me sweating a little.

The crux of the issue seems to be this. When slowing to a very low speed, or almost stopping, it appears the transmission doesn't down-shift to 1st until you hit the gas again, thus causing a delay in response as well as some jerkiness.

Driving it around today I didn't notice it that much and I was paying attention. Maybe I'm getting used to it. It seems that slightly altered driving habits can alleviate a lot of it. The only time it's an issue is when I'm trying to beat something out of the gate which I try not to make a habit of. Now that I think of it, holding the brake while giving it some gas would probably "set" the transmission in 1st so it more ready to respond. I'll have to try that.

Right now, I'm trying to restore my headlight clarity and I've already botched the job once.

 

there is quite a diferencies between 3.0 and 4.2 N/A. and its not related to speed(both engines takes to speedtickets) I have tried those all three engines and after 4.2S/C there is no way would want 4.2N/A or 3.0- the diferencies from N/A to S/C is what matters and are hughe step. And thats its in normal SLOW city driving.
Friend of mine have tuned xfr with 596HP and its even more breeze to drive- hughe torque from 1200RPM. I have also tried direct injection 5.0liter vs min 4.2S/C and still prefer S/C

 

No-one has ever posted that they've done that swap on an S-Type. The computers make it non-viable.

 

yes i know 3 people who have done one or the other swap and all electrics have to be swapped as well ie bcm, security module etc. never an easy thing to do but it does get done i actually bought a v8 s type which should have been a 4.2 but when checked it was a 3.5 and the drop in power was actually noticeable when driving so i took it back to the dealer and got a refund for that one

 

are the headlights cloudy as that is a common fault which is easily solved and as for the lurch i think it is possible to reset the computer so that it then learns your driving style that may make things better for you

 

in which case look for an s type reg mw02ose which is supposed to be a 4.2 but is actually a 3.5 as that is the one i bought and returned

 

I'm doing a pretty good job of restoring the headlights. I've cleaned them all up and the yellowing is gone. I've been attempting to clearcoat one according to a video I found online; but I'm not using the same clearcoat and have have some challenges getting it smooth & clear. After about 8 coats including sanding off and redoing, it's not bad. Not sure I'm going to do the others. I've been working on these headlights for a week on and off. I wished they used glass instead of plastic.

As for resetting the computer, is that something I can do or do I have to take it in?

 

i have found two things that bring these headlights back to almost new the first is a compound called jewellers rouge which is a paste its very fine and with rubbing in and cleaning off gets rid of the clouding but the second does the same but with a bit more elbow grease is a fine toothpaste its much cheaper. As for resetting the ecu just remove the negative terminal from the battery and touch it to the positive for 30 seconds , reconnect and drive for approx 300 miles it will learn your driving style and set the trims to suit you as at the moment it is set to the previous owners driving style which may be very different to yours

 

No need/benefit in resetting the 'computer', not sure where the idea came from.

For redoing the headlights, the best results come from the kits that are sold at every car parts store, made for this exact purpose. I use the one from 3M.

 

I did try one of the cheap headlight restoration kits and returned it because it didn't do the job. I didn't like the price on the "good" ones although by the time I got done buying all the sandpaper grits, clearcoat spray, and some other supplies, I ended spending as much anyway. At this point the yellowing and oxidation is gone. They're not perfect but I'm done screwing with it. Put in way too much time.

 

the reset idea actually came from Duncan the only specialist jag computer engineer in the area who also lectures and teaches the computerization training on jaguar cars uk for jaguar. He also states that when a used car is sold through jaguar dealers they automatically reset the ecu's to allow the car to learn the new drivers style of driving due to the whole point of the ecu being for the car to set itself up to your driving style for optimum performance and economy for individual owners

 

I'll make a point of avoiding 'Duncan' if I'm ever in the area. He seems to be rather misinformed on many levels.

 

Don't be cheap and buy V12 emblem.\
Ability to count from 1 to 12 is necessary for a Jag buyer.

 

Doesn't do that on S-Types. Avoid this Duncan person.

 

i will be sure to tell him he has been teaching the jaguar technicians wrong all these years.
he has only been training them for about 15 years