I have a 1990 740 turbo wagon that won't start. It has been overheating and after the last time it did this I let it cool down and now it won't start. I have no power to the fuel pumps ( I did bypass the relay and I am getting fuel to the engine so the pumps work) but even with getting fuel to the engine with the bypass there is no spark. I replaced both boxes under the drivers seat with no result. You know how it is with buying electrical parts- no returns. I am trying to avoid the Volvo shop if possible. The diagnostic codes show no ignition faults but the fuel injection codes are not showing anything at all. The suppression relay seems to be working and I am starting to get frustrated with the whole process. Any suggestions would be greatly appreciated. Thanks, Jay