Bogging down just as you hit the gas? Bogs down worse at low RPMs? That was the pattern on my 1992. Between a Volvo shop and me, we checked out lots of possibilities. Turned out to be the ECU.

Your description isn't exactly like my problem. On mine it was mostly, but not totally, consistent.

1. Try disconnecting the battery for at least 10 minutes. The ECU maintains memory states even when the ingnition is off; once you disconnect, there are capacitors that may take a few minutes to discharge fully. If that changes anything, even temporarily, it's more likely to be the ECU.

2. Swap the unit out. You know any other Volvos that might lend you an ECU for a few minutes? Other people on the board may be able to tell you if there are any other ECU #s that exchange with yours. Get the number off your unit and search the archives. You can do a Google "advanced search"--just enter the last three digits of your ECU's Bosch number (0 280 000 xxx, more or less) as the Keyword, then limit the search to the domain "brickboard.com". It worked for me.

Good luck.

Doug Harvey