2001 xk8 Convert. Have a P0442 and also had problems filling tank last time. Found tsb about plugged vent and rust also holding valve open. Thought that would be My issue , car on lift tonight looks like tsb has been performed. Removed ccv to inspect and check hose that also had been posted as cracking causing the code. Hose ok by all appearances. Valve was stuck closed. freed valve and cycled repeatedly with 12volt to pins seems ok now. That explains the hard fueling. So reset codes and drive cycle monitor is not complete for the evap system. Just recently introduced to mode 6 diagnostics on OBDII. So on My code reader when I access mode 6 I don't have the Jag details and the tests are in code. Test $07 show a min reading of 7f in hexadecimal which is 127 and a reading of 19 status low. So who has the Jag mode 6 info and any conversion factors needed as I know all readings are not direct and sometimes must be converted.

 

I do not have the code conversion info but if you want to force the Evap. Emissions test to run this driving sequence will do it:

-Gas tank about half full.
-Drive around for 10-15 minutes and get the car well warmed up.
-Turn off engine for 5-10 minutes.
-Restart engine and idle for 13 minutes...do not touch the gas pedal during this period.
-Then as soon as you can, get on the highway and drive at a steady speed for over 6 minutes.

If you have not cleared codes, and there are no other faults, a pass of this test will register a P1111. If you get that, problem solved.

 

Code cleared , drive cycle monitor complete for evap system. Problem appears to have been a stuck ccv. Still looking for mode six info. Found a good Ford site , have to finish browsing and see if info will work on Jaguar. Been out of the Auto business since the early 90's and have just now bought a scan tool. Have been able to survive without it. On reentering this side of repairs mode 6 really interests me. As Johny 5 said , Input need more input need to learn more.

 

A lot of mode 6 data is on jag's TOPIx site (with the workshop manuals), which is quite cheap but not free.

Some tools decode it - I think AutoEnginuity is reasonably cheap for what it does.

(I don't know to what extent your car's PCM will have mode 6.)