I thought I'd share a couple tips and tricks I've learned now owning 5 of these cars and working on them myself. From detailing to timing chain tensioners - I've done it all myself (to save as much money as possible). These are my own experience and might not apply to everyone

For Supple Leather
Use a leather conditioner such as Lexol conditioner after cleaning. Coat all leather well and let the car "cook" in the sun for a day. Conditioned leather should be matte and not shiny.

ABS / TRAC Lights
Make sure you have a good/new battery and perform a hard reset (touch terminals together for 30 seconds- 5 mins). Clean and/or replace speed sensors they are cheap. If that does not work you can investigate further. Using a Dremel to cut the ABS box and solder the points is actually very easy, so don't be scared to do it. You can't just order a new ABS module because they are programmed to the original car they came from, and you will have to go to a dealership and mess with programming ect. Not worth it imo.

Collapsed Front Shock Absorbers
Not a crazy job but makes a huge difference! Once you do one side the other will be a breeze. Definitely have an impact available for the job. I went with Peter Hobman's shock absorbers- buy a rivet gun for this kit! DO Not purchase the "OEM / URO" absorbers, these deteriorate fast. Peter's kit is about $100-120 after shipping, which is much cheaper than uro anyways. If you don't buy the damper as well, I would suggest buying the lower bushings as they are usually very worn out.

Tint
Tinting your car can be a great way to preserve the leather and plastic in the car. Check the local laws so you know how dark you can go. I chose nano-ceramic on my Jag. Looks great and the car is no longer a fish-bowl.

Exhaust and Drone
I have an XKR which currently only has cats, an X pipe, and straight pipes back. Sounds great, super loud, but a little trumpety at 2500 rpm. Your exhaust tips will also affect how the car sounds. The rearmost boxes are the ones that control drone. To avoid, you can hack off / replace any boxes before that, including the squashed over pipe. X pipes sound raspy, and H pipes give a more classic muscle car growl. X pipes improve flow and will give a couple more HP over the H pipe. I did a lot of research before designing my prior XK8's exhaust. Three box delete and H pipe- no drone!

Misfires, No Start, Convertible Quarter Windows
Always make sure you have a good battery if you have no start issue. If the car has been sitting for around 2 years usually a fuel pump will have gone bad, resulting in a crank no start. Misfires in my experience are almost always a bad coil pack. Pulling the packs and spark plugs are easy! You can also use a fuse jumper (a wire with a pin on each side) to manually jump fuses. This works to test (listen for) the fuel pump operation, as well as open and close convertible top quarter windows should the top get stuck down/up.

Supercharger Oil and Power Steering Fluid
Both are super easy "suck old fluid up, put new fluid in" changes. A syringe with different sizes of tubes + fluid is all you need to do these jobs. Can be done in half an hour and is something you can do yourself easily.

Upgrades and Performance
If you have an XKR, you might want to consider upgrading the intercooler pump for better cooling. The Bosch 010 intercooler pump is what I used, and you can solder the plug connections from the old pump. There are several tutorials on YouTube that go in-depth on how to do this. It's not very difficult but added cooling is super beneficial since our engines run so hot. XK8's can also upgrade their water pump housing. The XKR also has an upgraded water pump, which replaces the plastic fins with metal ones.

Intakes
Intakes make a big difference but here's how I distinguish the several kinds. The X100's already have a great cold-air intake setup, but can definitely be improved. Any cone-style intake filters WILL suck hot air from your engine bay resulting in a loss of HP. Unless you have some sealed box- it will happen. They sound absolutely amazing however, so one may choose sound over a couple HP. The Mina Gallery intake tube and cone filter is not amazing quality- the bracket is cheap and it wiggles and flops around if you shake it, and the cobra-neck silicon tube is just plain silly. Our stock accordion-style intake tube muffles sound and is small / hinders air flow. The Mina Gallery tube is larger and allows for more flow, however the metal tube does heat up. K&N are wet filters which can oil up / dirty / damage your MAF sensor. (I haven't heard many cases of this.) The best set-up for HP is a large intake tube (such as one from Mina Gallery) and a hi-flow air filter in the stock airbox. You can unlock 15-20 HP from this!

 

Great stuff and thank you! I'll be applying some of these upgrades as well to my XKR

 

had a crap tint failure on one window,,,,,new exhaust less two sets of mufflers,,nice sound,,quad stainless tips look great