Jaguar XJ8 Throttle Body Replacement

For the last few weeks I've been chasing the P1229 code, which relates to a throttle body motor failure.  In the usual fashion this meant that the car had been falling into failsafe/limp home mode randomly as I was out driving.  I wasn't entirely sure how to approach this project, but realized that I'd save a ton of money by switching out my throttle body for a salvaged one.  After getting the run around from the dealership, I also quickly realized that I'd be much better off if I could do the job on my own.

Thanks to the thorough instructions and pictures posted by members on Jaguar Forums, the job quickly seemed less daunting.  I actually got a very helpful reply that I used to do the job.  See the complete list of instructions here.

After completing the job the throttle motor was noticeably more responsive and the code didn't return, however I fear that the throttle position sensor may still need replacing once my other salvaged part arrives.  If all of this sounds a bit familiar, it's because last fall I replaced just the throttle position sensor after experiencing somewhat similar problems.  

Without question, the throttle body seems to be the weak spot for the '98-'03 Jaguar XJ8, but at least salvaged parts seem widely available on eBay at a fraction of the cost of buying new - Jaguar wanted over $2000 for the throttle body alone.  Follow the instructions I've linked above, and hopefully once my salvaged throttle sensor arrives everything will truly be back to normal.

The replacement seemed like a huge project at first, but it wasn't too bad.

The old throttle body in the back, the new salvaged part in front.

Here's a look after I completely removed the throttle body.

A few bolts, electrical connections, and coolant lines were detached.  You can actually see I used AA batteries to plug the coolant lines so they didn't leak everywhere.

Here's the job completed with everything back in place.

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