I own a 1984 jaguar xj6 VDP, I recently have come across that my car is a lot louder than usual and there's a knocking coming from underneath it whenever I'm above 40mph and I let off the gas. The knocking isn't there if I'm pressing the gas. I don't really know much about cars but it was my grandpa's car and be passed away. I'm hoping to get this fixed, if anyone knows your help would be appreciated.

 

Exhaust pipes have moved out of alignment, as in some of the rubber bushings have gone Awol.

Transmission mount is more likely the culprit.

Have a read, YES, I know it starts as the the V12, but the 1/2 engine version is near the bottom.

BUT

The basics are identical for both.
That "Cotton Reel" has a 10 year life TOPS.

 

I appreciate your response. Since I'm not too mechanically inclined I probably won't work on this myself I'm too worried of making things worse lol. How much do you think this would cost to repair?

 

No idea, I am down here are you are up there.

I reckon 4 hours as a guess.