I'm trying to trace down the cause of my emissions problems on a 87 244 that I just recently bought. The car runs well with plenty of power but fails the emissions test with HC at twice the limit and Nox at about 5.000 with the vacuum advance line plugged (needs to be under 2.ooo to pass) - anyway I decided to check the timing and couldn't even see the mark on the pulley with the timing light pickup on wire numeber 1 (closest to front). Out of curiosity I tried putting the timing light pickup sensor on the wire for cylinder 2 and found the timing mark to be right on the money (12 derees BTC). cylinder 3 is also exactly on the mark and on cylinder four the mark is not visible (just like cylinder 1).

The wires are connected correctly to the distributor and the respective spark plugs.

So now I'm really confused! How can the timing be so far off and still run smoothly? Any help is greatly appreciated!

By the way, the head was recently rebuilt (shortly before I bought the car) by a DIY mechanic that was definately not familiar with a Volvo.

Thanks

Jim