Where and what do I need to unplug to check and adjust the timing on my 2.3L 1991 940 GLE. Just trying to verify the timing as I'm beginning to bring this car back to driving condition. Thanks for any help.

 

There is no need to adjust the timing on these cars. The timing is controlled by the computer.

I tried on my first 240 and it was really strange when I loosened the distributor and turned it but the strobe light showed no change on the timing mark.

 

cars that have a hall effect sensor in the distributor ... the timing can be adjusted. Cars with a crank position sensor (LH2.4) can't be adjusted.