Good Morning All:

My X-Type has always been touchy about closing the gas cap just right. Too few, or too many 'clicks' when tightening it, and I would get a check engine light, which would de-code as an Evaporative Emission Control problem. Of late, though, it has become regular. A new, genuine Jag gas cap has not solved the problem; I can clear the code, and the light will stay off until I start the car for a second time after clearing. It will stay out for hours, but re-appears within about ten seconds of a re-start. Any ideas where to look next?

 

Evaporative System – Diagnostic Flow Charts

http://www.jagrepair.com/images/TSB/...e%20System.pdf

 

Thanks, Santer. That should keep me busy for a bit!

 

Robert, I had this issue on my car. I bet you like to fill the tank up as much as possible. Your problem most likely lies in the purge valve. If you open up the hood of the car, look to the left of the master cylinder. You will see 3 plugs there just under the lip of the cowl. 2 of these plugs go to the O2 sensors. The 3rd one goes to the purge valve. You will also see 2 vacuum lines connected to the purge valve (one comes right off the top of the intake that you will find will most likely be in your way). You can remove the 2 vacuum lines, undo the electrical connector, then you can slide it to the right (towards the brake booster). At this point, it should be able to be removed from the vehicle.

Get yourself some carb cleaner and squirt it in the 2 vacuum line openings. Flush out the purge valve. Do this 2-3 times and then reinstall. That should fix your problem.

 

 

Thanks, Thermo, but to no avail ! Can I apply 12 volts across the two terminals on that valve, and see if the valve is operable?

Since I said 'GoodBye' to my XK8, the X has stepped up its game in the code dep't, and now seems to think there is no input from the right rear wheel speed sensor as well!!?? I removed it and cleaned it, although it was pretty clean. The toothed wheel looks fine (a little bugger to get at!) A picture of the replacement item seems to show a connector, but I'm not sure where it is located. Under the rear seat, maybe?

 

Robert,

The purge valve is a 12 volt solenoid valve. You can test it by applying 12 volts - after you first disconnect it! This valve may have an internal surge suppressor or diode. So, to be safe, make sure you apply positive voltage only to the terminal that normally is connected to the green/blue wire.

The connectors for both rear wheel speed sensors are located under the rear seat bottom cushion. To remove the seat bottom cushion, pull up (vertically) from the front edge of the seat cushion at each side.

I recently changed my driver-side ABS sensor to fix an intermittent ABS code issue. Very straightforward job once you get to the connector. I bought my sensor at Auto Zone for somewhere around $55 with lifetime guarantee.

 

Thanks, Mark

Rain day tomorrow, so I'll wade in a bit deeper.