All right, I am having an issue with the RRC.
Check engine light off, the car will buck, almost stall, cough stutter and surge. It is driveable, but barely. When the EFI light comes on, the car will idle a bit fast, then settle down and drive. Gets about 12.5 MPG at 75 MPH freeway at this time.
My first thought was, I have an issue with a sensor/connector somewhere. As far as I know, 02 sensors are original, MAF is not, etc..and the computer is a later 90's Classic.
And I read on RR.net : The EFI light is designed to come on when the ECU detects high engine coolant temperature (this uses a different sensor from the one that drives the gauge) or a malfunctioning Throttle Potentiometer, Oxygen Sensor or Air Flow Sensor
SO, great minds, thinking of a 1988 RRC, what sensors are active but would be inactive when the Limp Home Mode kicks in? If I can figure that out (as it runs fine once the light is on) I can focus on those sensors/connectors first and inspect, clean, and/or replace and test.
Anyone have any idea?