Are there any vacuum lines going to the transmission or is that old school stuff? I've got the good old p0171 and 174 codes and i'm going to smoke test it.

 

No but vacuum does play a part in how the transmission shifts. I have a thread or post about it somewhere here. I just cant seem to find it.

 

so then there must be a line going to a module, or does the vacuum get registered some other way? i'm just trying to find all the areas i should be checking for a vacuum leak causing the codes. let me know if you find the thread.

 

No vacuum line going to the transmission in my 2004.

 

No such lines so just follow the many threads about those codes.

 

Just follow Rick's excellent vacuum line thread; forget about the xmsn.

 

https://www.jaguarforums.com/forum/s...ics-faq-52720/

rick - is this your thread?

 

Why yes, yes it is!