Just bought a used '97 850 GLT with 70K miles. After a week or so, got check engine light. Mechanic said that there were several misfire codes, both random and specific cylinders.

He put in factory plugs, changed distributor cap, rotor. He said plug wires were in fine shape (were pretty new according to previous owners records).

So I took the car home and a few days later, light comes on again. Mechanic says same codes. He investigates further.

He calls me to come have a look-see. The Volvo DEALER that had installed the new timing belt six months ago had not lined up the camshaft marks correctly on one of the gears. It was off the mark by about 4 teeth. I also had a leaking hydraulic tensioner.

He also suggested it may be a good idea to replace the water pump, since he is taking everything apart anyway, so only cost would be for the part, but that was up to me.

Mechanic says this is most likely causing the misfires, and it needs to be re-installed correctly.

Does this make sense to you guys? Just want to make sure I'm getting the right info.

Bob