I just returned from my California Smog Test, for my 1999 XK8, and as I hoped and prayed it would pass, (of course it did NOT), my report says all passed except for :

Malfunction Indicator Lights..........Fail
Fault Codes P0121 TPS Sensor A Range/Performance Problem
P0328 Knock Sensor 1 High Input

Can any of you smarter than me, Jag Enthusiasts, please guide me in the right direction. I have taken some great advice and direction from this site, saving me loads of money already.

I am not a mechanic, (not since I could rip apart and reassemble my 1969 Chevelle, 4 speed, 350 small block lt1 engine, when there were no such things as sensors and micro chips telling my car how to act), but am perfectly capable of following instructions, especially when it saves me $$$.

I would really appreciate direction, so I can get back to loving my driving my XK8!

THANKS DJ PAUL E

 

Sounds like you had a check engine light on, and either the light itself wasn't illuminated (someone intentionallydisabled it, or bulb out -which is rare), and those two faults were present in the computer. The knock sensor surely would have triggered a check engine light for you to notice.

The TPS is part of the throttle body, and have been known to fail over time. I would clean the TB, and the TB plug/harness connector, then clear the codes. Oh, you might want to adjust your throttle cable too, there's a DIY procedure in the FAQ thread, but you'll need another 5 posts to access most of those pictures...I think. It may be a youtube video too...but easy to do in the garge.


As for the knock sensor, I would swap the #1 with the #2, clean both connectors really good with electronics cleaner, do the hard reset and clear the codes and see if it reappers. If the code follows to the Bank #2, well its sensor itself gone bad. If it stays on the bank #1 side, its a wiring problem most likely.


Nothing to get too worried about until you do some basic maintenance and look for reappearing codes. However, if you Check Engine Light isn't coming on when you turn the key and start the car to test all vehicle modules and lights, then you've got a bigger problem to hunt down.

 

Hey H2O boy, Thank you for your prompt advise regarding my SMOG situation.

First: "Check Engine" light is functioning. A couple months ago, it would come on after going into "fail safe mode" or "restricted performance". When this started, simply turning off the engine, and restarting, would solve the annoyance, and the Check Engine light would reset itself. It did eventually digress and started to occurring more often, so after checking posts here, I cleaned the MAS and the TB connectors, which seemed to solve the problem for a while.

Last night after posting, I researched and found the DIY instruction threads/video for adjusting the throttle cable and immediately adjusted the throttle cable. Oh FYI upon driving home immediately after the Smog Check, the check engine light was lit, but now after adjusting the throttle cable, (I have only driven 2 short trips), the check engine light has reset it self and is OFF, and the car has not kicked into Fail Safe or Restricted Performance mode and I think I notice improved performance.

I think I have addressed everything you so kindly replied to my call for help.
I truly appreciate you sharing your Jaguar knowledge and experience with me.

If my Jag runs good without going into fail safe or restricted performance modes for a reasonable time period, should I go and get the SMOG RE-tested and do you feel confident it should pass?

Again, THANKS ever so much for your time, and to this web group ...I am so grateful there are so many kind and giving people in the world that share their fondness of JAGUARS!!!!

Wishful thinking, DJ PAUL E

 

go to the auto parts store and they will (for free) scan the car and get codes. If there is no other P codes besides the P1111, then you should head straight over to get your inspection done and smog testing finished.

If the P codes still show up, clear them, and drive for awhile to get those 'cycle's completed, then say in a few weeks, go get your codes read again. Evaluate then.