My engine was pretty dirty, even had some splash marks on the "Jaguar" covers, so I popped them off and cleaned everything by spraying a cleaner onto cloths and wiping by hand. Took about an hour including a little silicone dressing on the valve and Jag covers.

I just got the car behaving correctly so I didn't want to go in there with anything more than that!

 

Looks good. It also looks like you are missing one of the two bolts that
hold the plastic air TB tube onto the TB. I clean under the hood with WD40. Works great, it's cheap, and leaves a nice soft shine.

 

Thanks, cleaning it up sort of finished off this latest round of struggles with the car.
I went out and looked at the TB tube/TB attach point, and the holes on the rear side of the tube aren't threaded and the flange doesn't seem to attach to anything. I attached a pic of the area I believe you're talking about. Please advise if it's somewhere else.
I'll hit some spots with the WD as well, a little aesthetics goes a long way in an engine compartment!

 

Indeed you are missing the bolts, should be 2 x short 6mm flange bolts holding the tube on...

1 as you have pictured and 2 about along the centre line of the TB at the back, you will see the hole.

 

Ok, I'll definitley take it in Monday and have a tech address that. Thanks guys!

 

Looks like the wrong throttle body tube was installed. The Jag tech says it's the tube for an XJ, not an XK. Same engine, but different installation! I stopped by the indy shop that put it in and they said they would get another one as soon as they look up where they got it from.

 

I've used the same under hood cleaning procedure on all my vehicles without incident: Warm the engine, cover the alternator with a plasic bag, douse the electricals and connectors with WD40 or the like, apply foamy Gunk or Simple Green, gently brush where accessible then rinse (avoiding direct spray at anything electrical), then leave the hood up until dry. Remove the plastic bag on the alternator and take a short trip to dissipate any trapped water. Mist with Armor All and that's it.