Hello all. Needing a little help or just a question answered I guess. I have owned my 1990 Jaguar xj40 for 6 years and I love it. Recently I found a 1991 Jaguar xj40 Sovereign that has been sitting since 2009. The original owner bought it new, put 81,000 miles on it then passed away. It sat in his driveway since he passed in 2009. His son sold me the car which I had to tow home as it wouldn't start. Going over the car to trying to get it going again I realized that the spark plug wire order on the distributor cap was different than my 1990. I know the engines are the same and actually compared to my 1990 it is exactly the same under the hood. The firing order is the same, (153624), but the #1 starts in a different position! on my 1990 the #1 wire starts in the 5 O'clock position while the 1991's #1 wire starts in the 10 O'clock position? I even took the #1 spark plug out, (First plug front of engine), and checked when piston is top dead center the rotor is on the #1 wire position and it was.
My question is why are the plug wires in the same order but in different positions on the distributor cap?

 

Assuming the distributor and cap are the same, my guess would be that the #1 TDC would not be on the compression stroke.

IMO it might be worth trying re-locating the plug wires to agree with your own car and see if that makes any difference?

Just guessing here, anything is possible!

Larry