N6 JMX

Here's a bit of a dichotomy for folks like me that prefer to stick with the development tyre as designed for the vehicle. For the New XK, the X150, the development tyres were: Dunlop SP Sport Maxx and correspondingly with a "J" for Jaguar spec. Pirelli P Zero, with either a "JRS or J" spec, again fro Jaguar. I typically replace my tyres at 5 years old, irrespective of the wear during the period - obviously if they were worn down, replacement would have been sooner. In 2025, it was time to replace all 4 tyres on an age basis, but when I started to search for replacement Dunlop SP Sport Maxx J spec, which I have had fitted to the car from new, then there appeared to be a lack of front tyres in the J spec - 255/35/20R. Rears in the correct spec at 285/30/20R were readily available. After some digging I was informed that Dunlop (now a part of Good Year) have ceased production of the front tyres in the correct size and specification. The alternate would be Sport Maxx RT2, which I understand are a little bit of a softer compound with the added disadvantage of being simply a "generic" sporty tyre. I actually believe that there are better generic sporty tyres out there if forced down that particular road. Undeterred, since I wanted 4 matching tyres, I spoke with Pirelli and found that they have the reverse problem, suitable P Zero for the fronts, but no such luck for replacement rears. Pirelli also advised that their production schedule look ahead, which is typically 8 weeks, was not indicating that the rears with J spec were going to be available anytime soon. After much thought, I removed all 4 wheels and tyres from the car and carried out a thorough inspection. My conclusion was formed from the basis that the front tyres were actually in perfect condition, having nearly 7mm of tread evenly across the section, so around 1mm of wear in 5 years and 15,500 miles. The rears however were worn down close to the wear bars, so some 7mm of wear in the same 5 years and 15,500 miles, and therefore rightly due for a change on wear. At least the rear wear pattern was completely even across the tread section. I have elected to change only the rears for the time being and maintain a watchful eye on the fronts, fully accepting that if I do encounter a front tyre issue, I will be back to square one and looking for 4 x replacement tyres once again. I am sure that the fronts will begin to affect the handling by becoming harder as the compound ages past the 5 years, but despite wearing out the rears completely, I am not pushing the car as hard as I might once have. Unfortunately tyre choice is very much a personal thing for a lot of folks, but my choice has been, to date, to stick with the development tyre despite its technology being over 20 years old - although manufacturing processes and constituent compounds will have been updated since 2005 during its development. Also tyres are not something that one can try before you buy so moving to a replacement brand, premium or otherwise, is always going to be a bit of a gamble and one has to seek out personal experience of the Jaguar community for alternative suggestions. I understand that a lot of folks cannot see past Michelin, in the various sporty guises, but I have never had good experience with Michelin, so historically i stay away from them, but what have others out there found? N6 JMX

Hi Mike, it really depends on "how damaged"! The splitter will unbolt completely - 5 or 6 Torx bolts i believe. Once it is off you can really examine the damage and any decent body shop should be able to offer advice on a suitable repair. Alternatively, you can approach the various specialist Breakers such as Autoreserve, but if you have damaged yours then any involved in frontal impact damage are going to be mangled. N6 JMX

Hi Karen, if you have gotten into the car, then pop the bonnet and fit a secondary battery or booster pack to the +ve and -ve terminal posts under there. Don't do anything else other than then use the boot switch to open it. If need be, you can also use these posts to charge the main battery, but it sounds as though that has gone past the point of no return and needs to be replaced. N6 JMX

Hi Neil, the symptoms you are experiencing are most likely caused by the battery in your XK. In a modern car, like your XK, the battery's ability to start the car is no longer the definitive that the battery is good, even if you have it fully charged. The reason for the faults appearing and reappearing is the spikes to the 12V system caused by an old or failing battery. If you fit a replacement battery, the faults will be cancelled and not reappear. Folks like me consider the battery in my car as a consumable with a life span of just 5 years. Beyond that age, the battery is not capable of sustaining the stable voltages that the car's electronic circuitry needs. N6 JMX

Hi Mario, have you tried "Swallows Racing" in the south or "DCR AutoParts" in the north? Both should be able to give you a steer on the parts you require. Pop either into your browser for contact details, or come back here and I can send you links. N6 JMX

Hi Adrian, welcome to the wonderful world of Jaguar XKR motoring. If you are interested in meeting up with like minded folks, look up the XKCC at the following link. Home | XKCC N6 JMX

Hi Lennart, have you confirmed that the water pump is working correctly? A dry / empty hose would suggest that no circulation is taking place. Additionally, with an unknown history, you may wish to consider emptying the entire coolant system, flushing the waterways fully and then refilling with the correct strength and formulation of antifreeze. Mixing antifreeze types can create gelling and therefore blockage of the waterways. N6 JMX

Hi Peter, when a misfire occurs there should normally be stored codes (DTC) that can be read by a suitable OBD code reader - diagnostic system. Ideally, this should either be the Jaguar Diagnostics or the Auto Logic system. These codes are key to fault finding on a Modern XK. If the fault is intermittent and one coil pack and injector has already been replaced, there could well be a waterfall effect for other coil packs and / or injectors - they are all of the same vintage of course. As an aside, if your mechanic is not familiar with Jaguar's numbering, he may well have replaced the incorrect offending parts in the wrong location. The following info is from the Workshop Manual: References to Bank-1 and Bank-2: References to Bank-1 and Bank-2 are made with regard to the engine. When viewed from the flywheel the right-hand bank will be Bank-1 and the left-hand bank will be Bank-2. Cylinder numbering: The cylinders in each bank are numbered from 1 to 4, with number 1 at the front. Comment: from this, which is cylinder number 2 or 6? Requires additional definition In other words, have the correct parts been replaced in the correct locations? Another possible cause of a misfire is a vacuum leak, which can be notoriously difficult to locate, but a smoke test of the pipework could show up a possible leak for investigation. Hope this helps with the fault finding. N6 JMX

Hi S-type Driver, are you sure the water ingress is "new", i.e. since you have had it standing outside in your ownership and not water that was already in the well when you acquired the car? Dry out the well and surrounding area and leave it to stand as before, but this time coat the whole of the boot seal with a light dusting of chalk powder. Alternatively, try a smoke generator placed inside the boot with the boot lid closed. It may simply be a case of the boot seal has lost some of its elasticity and needs a bit of packing. Ed China fixed a poor seal on the door of an Aston Martin by packing a new piece of rubber inside the existing door seal. N6 JMX

Hi Geoff, this is one of those "piece of string" questions, without a definitive answer. It is compounded by the Jaguar indication that the gearbox is "sealed for life", although the cynics amongst us would say that hidden in the small print of this indication is "sealed for the life of the gearbox that we (Jaguar) have warranty liability for". Another school of thought is that the gearbox oil should be changed at 60,000 miles, however there are question marks associated with that concept. For starters there is usually not a drain plug so the oil needs to be vacuumed out. Then by measuring how much you have sucked out, you replace that same amount, but then there is a complex process of leaving it to stand on a level surface overnight, then bringing the gearbox to a specific temperature and removing the fill plug to top it up, until the new fluid just dribbles out of the fill plug. Then you are "good to go", but another level check is encouraged. Having gone to this effort, of course you can only remove around 50% of the contents of the gearbox oil fill, as there will be an amount in the oilways and torque converter that has not been removed and therefore you now have a mix of original and replacement fluids. Are they compatible? Unless your gearbox is showing any signs of lumpy operation, or sluggish changes, you may well consider it best to leave well alone, but it comes to personal choices after having done the research. Let us know what you decide. N6 JMX

Hi Caio, if a replacement engine is now the thinking, then I suggest you speak with a Dave Roche at DCR AutoParts, who specialise in new and used replacements for the X100 (your model). You can find Dave's details at the safe link below: DCR AutoParts - Independent Jaguar Parts and Accessories Specialist Alternatively, there are specialist breakers for Jaguars such as Auto Reserve. N6 JMX

Hi Duane, you have found the Forum pages okay and if you scroll further down you will come to a Market Place section, where you can post in the "Jaguars For Sale" tab. N6 JMX

Hi Alexander, If you explore a little further down the pages of the Forum, you will find a "For Sale" section where your E-type for disposal would be better placed to find a potential buyer. It is currently in a section of the Forum where the addition of a new posting will take it off the front pages and very few folks will think to check the technical areas for a car that is for sale! I would also respectfully suggest that you need to be a bit clearer about the whereabouts of the location of both yourself and the car. Your profile information indicates that you are not in the UK, yet the car appears to have a UK registration plate. You also don't provide any information that might interest a potential buyer, i.e. does the car run, drive and stop, if not when was it last road legal. Information regarding number of previous owners, service record and other pertinent details will also help stimulate interest. Additionally, there is no method of getting to communicate with you, other than via an open forum, which is not an ideal medium to sell / buy a car so you may wish to consider how people contact you. Just some thoughts to consider. N6 JMX

X150 wind deflectors are available from recognised suppliers such as Adamesh and Paramount Performance, circa £180 each. I got mine from Adamesh at least 15 years ago and it has been excellent. correct shape and can stay in place even with the top up. N6 JMX

Hi Kevin, first check has to be the tyre pressures, check all round to ensure correct pressures are maintained. Secondly, try the car on a different road, sometimes the carriageway can cause some weird feedback issues through the steering. Can you tell if the steering inputs are working correctly, i.e. car moves under steering control to change lanes properly? Check wheel alignment - all 4 wheels specifically, especially if you have been in contact with potholes recently. Whilst the alignment is being checked, have the mechanic check for any play in the bearings and bushes. Any play in the system can cause the front end to feel "woolly", or floaty. N6 JMX

Hi Martin, welcome to the wonderful world of Jaguar motoring, especially nice in an XKR. E5 petrol is the fuel of choice, with 98, 99 and 100 available depending on forecourt used. The XKR will of course sort itself out if you need to use E10 fuel, but most folks shy away from this for a wide range of reasons. N6 JMX

This is the workshop image of the fuel tank and fuel filler pipe on the X150 model. If you open the image and zoom in, you will see that the vapour pipe from the fuel tank to the filler head, connects to the filler head in the funnel element of the assembly. If you don't fully insert the fuel pump nozzle into the filler head, then the outcome should be obvious. The standard petrol pump choke back pressure is normally set VERY low so as to prevent fuel spillage onto the forecourt and across folks paintwork. N6 JMX

Hi Philip, we are each entitled to believe what we want. My experience has shown that it is not the fault of the car. N6 JMX

Hi Peter, so if it was replaced in 2019, it is now in the consideration zone of needing to be changed (5 and a half years old), irrespective of what a garage tester says. Your choice, continue to experience problems generated by a battery not providing the stable voltage the sensitive electronics in the vehicle require, or change the battery and eliminate that issue for peace of mind. Only you can make the choice. N6 JMX

Hi Ryan, check out the site for Mr12Volt at the safe link below. Mr12Volt Car Interface N6 JMX

Hi Peter, sorry but it really is time to invest in a replacement battery - see all the reasons in the above thread. If your battery is original - Jaguar sticker in place - it is well past its best. N6 JMX

Hi Folks, in all of these cases the fault does not lie with the car but the petrol pumps which have their choke cut off pressure set too low. The fault should be notified to the attendant in order that he can log it as a fault for rectification during the next pump maintenance cycle. I appreciate it is frustrating and that their are some "apparent" tricks to circumvent the isue, but believe me, this is a well researched issue and it is always the pump at fault. N6 JMX

Hi Steve, unless there is a fault developing in the steering rack, which is unlikely, I would jack up the front end and undertake the lock to lock reset with nil load on the front end to see if that makes any difference. If the steering position sensor goes, then the input feeling is very different. The turn in feels light and there is no self centring return, i.e. you need to manually rotate the steering wheel back to the straight ahead position. Whilst the front end is off the ground, check the play in bearings and bushes just to be sure. Otherwise, enjoy the wonderful world of Jaguar motoring. N6 JMX

Hi Dominic, good that you think your imagination is playing a part in your issues, but keep an eye on it. It could be something as simple as a slight air leak on the inlet side, which seals up when the engine warms up. A smoke test might reveal a culprit, but remember to do it with a cold engine. N6 JMX

Hi Tim, beautiful looking machine. The first port of call for any history research should be the Jaguar Daimler Heritage Trust (JDHT), who hold all of the original build records for all Jaguar, including SS, cars since 1931. One can apply for a heritage certificate for your vehicle and you can see more by following the safe link below: Jaguar Daimler Heritage Trust N6 JMX