I don't think you're wrong about the fuel delivery if you've measured the rail pressure. The fuel odor could be a leaky injector; when I've experienced that, it is not only hard starting cold, but runs a little rough for a minute or so as the excess fuel gets dissipated.

With the OBD mode 3 (works in Regina too right?) you can open up the injectors to simulate that. When I've tried that with a gauge connected, the residual pressure shows the drop. Another clue might be the oil smells of fuel; dipstick is high.

That little bit of resistance difference surely doesn't explain the ECT code being set, so maybe that is a clue. The thermistor doesn't normally fail by changing its characteristic but its packaging and connections fail from the corrosion environment making it intermittent or just plain open circuit, especially those dual units like yours referencing common to the case in the head. I just mentioned checking the voltage because it is easy to do that without disturbing the sensor.

I figure most second-source arrangements are for competitive reasons, but Volvo's concurrent use of Bosch and Bendix is so short-lived that it makes the Rex/Regina an anomaly. The real story might be an eyebrow raiser. One major difference is Regina's ability to be reprogrammed in the field.




--
Art Benstein near Baltimore

Real Engineers wear badges so they don't forget who they are. Sometimes a note is attached saying "Don't offer me a ride today. I drove my own car".