I had a problem when it rained resulting in the distributor getting wet. The rain water was entering the engine compartment through the bonnet / hood seal.
I put a piece of carpet over the distributor which solved the problem.
I don't want to leave the carpet in or get the seal repaired because of cost, can I buy a cover for the distributor.
What's the seal look like? I don't recall my 740 even having one, how much could it possibly cost to buy a new one? Have you checked junkyards?
I had what I thought was the same problem, wet distributor causing a misfire whenever it was wet outside. By coincidence I discovered the real cause, which was the T piece in the washer pipes. The rubber valve had perished, causing an arc of water to come out of the top of the T piece which was aimed right at the distributor. Open you bonnet and use the washers to see if that is happening.
Stuart
By the seal I am referring to the rubber seal when you open the hood / bonnet that runs right across the with of the car
Get the seal replaced, it is only a strip of similar stuff to the boot (trunk) seal and shouldn't cost more than $5 (£3), less from a scrapyard (wreckers yard).
Cheers, Peter.
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