Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Welcome to the new NAXJA Forum!
If your password does not work, please use "Forgot your password?" link on the log-in page.
Please feel free to reach out to [email protected] if we can provide any assistance.
Or you can go to the dealer and buy it. I think i paid between 40 and 50 bucks for one but there is a little known secret. On the 87-90 XJs there are two CPS to choose from. There is the standard one and the high alt version.
The standard works well at normal altitudes while the high alt gives you more advance so when you are in mile high city you don't have a major loss of power.
Also with our series of XJs, I own a 88 XJ, there is a knock sensor so the engine will retard the timing if it begins to ping. I can see no down side to installing the high alt CPS. At my dealer the standard and high alt were the same price, so more power for no additional cost... that a no brainer.
When you go to the dealer ask for Part number 53005421
If you are getting pinging with 87 octane then you need a new knock sensor. They are now available at parts stores, a couple years back it was a dealer only item.
You will find it on the driver's side of the block just above the oil pan and around cylinder #2. The old one will look like an oxygen sensor, has a white shaft and a fuel injector electrical connector. The new one looks like a little doughnut, here a pic of the new knock sensor http://www.partsamerica.com/product_images/img/NIE/DKS111.jpg
I looked and advance auto parts sells it for $65, I think I paid around $70 at the dealer for mine. So if you are running mid grade at 10 cents more per gallon then after approx 700 gallons of gas the sensor is then making you money. At 20 mpg that means after 14,000 miles. Depending how much you drive that could be a year or two.
Either way replace the knock sensor, sounds like your's is dead.