My S80 has been hard to start since I bought it 6 months ago so I brought it into the dealer for repair. After it was done, the dealer said it had a bad speed sensor and replaced it and he also pulled a fuel pump error code, so I had them replace that as well. It was still hard to start and sometimes runs rough and stallsand eventually it would not start so I had it towed to another deal who said he got the car running by rerouting the speed sensor wire, but could not diagnose the hard starting or stalling problem because there are no error codes stored (couple of weeks after the first Service)so he could not diagnose it any furthur!!. The Mechanic said that there was good fuel pressure, good injector pulse, no fouled plugs and good compression. It also had a good ground to the bell housing but may have oil and dirt between the bell housing and engine block??. Could there be a mechanical problem not monitored by the ECM? a faulty sensor not tripping an error code? Any suggestions would be great, Thanks, Tim