I love this site. This is my first Volvo, 200k 740 wagon, 1989 with automatic.

I have changed the engin mounts, now she idles smoothly.
Replaced water pump
Cleaned throttle body.
New flame trap and hoses.
New AMM
New Fuel pressure regulator
New timing belt and tensioner
Checked the temp sensor readings at the computer conector, normal ohm range for hot (running) temp and for cool temp.

Problem, I need to clean plugs every 1,000 miles.
Getting 14-18 mpg
soot out tail pipe (park next to snow bank and it turns black really quick.

As far as I can tell there are three possible items left to check:
1. O2 sensor
2. I havent checked the injectors for leaking
3. I havent swapped out the computer

An ideas on where to go next, I thought for sure it was the FPR, but she's still smoking after changing it tonight.

I'm thinking of going to the dreaded dealer, I hate to swap a computer just to try it?? Otherwise she runs good, but I need it to run well to start a new job next week.

Thanks