Shifter sometimes is a bit stuff from shifting from Park to either Reverse or Drive. Other times its loose. Car also "Jumps" sometimes when shifting into Reverse. And I will also get a squeal noise when I put the car into drive sometimes, usually on a cold start. The car shifts fine on driving, its mostly a idle thing. Thanks.

 

Only one way to know. Adjust the cable and see if that fixes it. If the cable can't be adjusted then it's most likely stretched and should be replaced.

Have you actually crawled under your car to have a look?

Did you check the cable mounting bolts on the transmission?
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Jaguar issued a revised selector lever cable so you might need to upgrade.

Here is some reading material.

bob gauff