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TITLE Cleaning the Jaguar XK8/XKR Throttle Body, MAFS, and Part-Load Breather
Project Time Required: Approx. 1 Hour
Last Update: April 11, 2008 – Version 2.5
Author Parts Store Items Needed Tools Needed Skill Level
Forum name: MrTexasDan
• Throttle Body Cleaner – *NOT*
carburetor cleaner. (Recommend CRC
• Electrical contact cleaner – Must dry
residue-free. (Recommend CRC brand)
• Flat blade screwdriver
• 8mm and 10mm nut
drivers or sockets and
• 3/32” (2.5mm) drill bit
• Vise Grips
• Phillips-head screwdriver
• 10mm wrench (for battery
I own a 2000 XKR. At 82k miles, I was experiencing hard starting and hesitation/rough running when the engine was cold. Also, at any engine
temperature when I stepped on the gas from a standing stop, the response was quite “jerky” and the car lurched.
After some online research, I set out to do a little maintenance that probably has never been done on my car (I bought it at 67k miles). Namely, I
cleaned the Throttle Body, Mass-Air Flow Sensor (MAFS), and Part-Load Breather Tube orifice.
After performing these steps (in less than an hour!), the hard starting and hesitation were gone, the throttle response was smooth, and I got
noticeably more power. I have added this procedure to my maintenance schedule for every 10k miles.
Many thanks go to Jeff Cline, SidVaga, and Bloodworm for their help and posts on this subject. If I ripped off any of your words, it is only because I
couldn’t have said it better. Any inaccuracies or omissions are my responsibility alone and not that of these fine people.
Corrections or suggestions for improvement would be sincerely appreciated.
This document may be freely distributed in its complete and unaltered state, with the author’s name and email addresses included.
• Clean connectors, hoses, and other parts as you go. This is good practice in general. Clean parts are happy parts.
• Under-hood plastic is notorious for being brittle and breaks quite easily. Handle with care.
• Care should always be taken to protect the paint while you lean over the fender. Wash dirt off the bodywork *first*, put covers on both
fenders, remove belt buckles, and watch for rivets in jeans or metal zippers, or other potential hazardous bits.
STEP 1 Disconnect the full-load breather tube from the big air intake duct by squeezing as shown. This releases the
tangs securing the tube so that it then can be pulled out from the duct. Rotate the breather tube out of the way.