Thanks for the helpful posts re: my last post about my 744T dying at 70mph on I-95. Basically, I have traced the problem down to a bad fuel relay circuit in the ECU by following the FAQ directions, so I can either drive around with the fuel pump relay jumpered (probably not that safe!), repair the ECU, or get another one (bug $$$). Does anyone know if/how to repair the fuel relay circuit of these ECUs? The one I have is Bosch part # 0 280 000 541. I read in the ECU FAQ that a person conducted the repair- but as I'm no electronics expert I found their instructions too advanced. Thanks in advance!

This may help in your search for an ecu. According to the Bosch Engine Management catalogue 2002 edition, the current ECU for your Volvo, 1989, 2.3L B230FT is a 0-280-000-591. I'm not sure what the difference is between this and your -541 which shows up in the 1998 catalogue. Perhaps some-one on the Brickboard can explain.

I would just grab a cheap one at a pick and pull. There is little or no demand for them because failures are so rare in that unit. Unlike some, like the 561.

I got an ECU from my local"U-Pull-It" yard for $25. According to the cross-reference they gave me, many years and even some 240 models will interchange, I happaned to find the same 91 turbo donor. I had a similar stalling problem, the replacement cured it!!

Good to know! I guess I better keep one around. The 544 and 554 out of the 240 might work? How about the 563 out of the later B230FT?