Hello

A while back I was driving somewhat hard in my '86 745 turbo. Car performed fine and then after easing off I noticed a misfire at low engine speeds.

Several wrong diagnosises later, I discovered the ignition timing was about 30 DBTC. Way out. The previous owner told me she "had the timing advanced" and I'm kicking myself for not checking earlier. Regardless, the timing was clearly the problem as adjusting the timing back as far as I could restored a good deal of drivability.

The problem is, I've turned the distributor as far to the driver's side of the engine as possible and can't get the timing lower than mid-20's BTDC. This is with the car warmed up and driven around.

I've been pouring over the 700 FAQ (thanks again Stephen) and the best lead I can come up with is the possibility that the coolant temperature sensor/leads are shorted and fooling the ignition computer into advancing the timing by 13 degrees. Is this a stretch of my imagination?

I checked the timing belt- it looks to be in good shape, and when I line up the crank pulley mark with the 0 pointer, the #1 cam lobes point up in the way I would expect if the piston was at TDC. I don't think the belt slipped, but if eyeballing it like I did here wouldn't notice a slip, let me know...


Any other input is welcome. This is one of those rare instances where YES the car worked great all the time and NOW it's not quite right all the time. I always thought it was the intermittent problems that were tough.

Thanks-
Dylan