Hi Grahame,
I am the member mentioned earlier who had a similar problem to yours, yes I was told to spray the ignition system with a fine mist of water in a darkened garage and to look for signs of arcing across from the leads to earth. This I did but no arcing was evident, however I did change the plugs and ignition leads which cured the problem and it now runs just fine. My car is a 1997 +4 with a Rover 820 T16 engine. I was passing Brands Hatch Morgan when this problem occured and Keith suspected that the leads and plugs were probarbly the original ones fitted all those years ago, so this replacement was long overdue.
Just for your information if you decide to change the plugs and leads, the plugs are directly under the bonnet hinge in the centre and space to work is very limited. The plugs are quite deep to reach, although I was told that this can be achieved I found it easier to remove the bonnet as the plugs were quite tight and getting purchase to remove them was frustrating, so off it came. Removing the bonnet is easy just the two bolts at the front and slide it out with some blankets over the wings etc for protection, putting it back is not too hard but better with a friend to help guide the rear fitting under the retainer.
Look for Rover 820 1997 ignition leads on Ebay and they are available for about £15.00 GBP.
Hope this helps.....
Rob...
