Atmospheric Pressure Sensor
 

I'm trying to track down why my car is all of a sudden running very rich. I just have a quick question about the atmospheric pressure sensor (next to the ECU under the kickpanel -- 1988 N/A).

According to the FSM, the sensor should read 2.5-3.5V at "high" altitude (defined as higher than 6500ft) and 3.5-4.5V at "low" altitude. My sensor is reading 4.5V -- however the altitude here is 4,500 ft above sea-level.

So is my sensor reading correctly (I've tried two and they both show the same reading -- are they both bad?). It seems to me that since I'm at a relatively high altitude, the voltage should be closer to 3.5V than 4.5V.

Could this be the source of my problems or should I keep looking? The thing is, my car started running way rich as soon as I moved up here from Seattle (which, obviously, is at sea-level).

Thanks for your help.
-Jonathan

(oh...and how do I know it's running way rich? A/F Gauge readout, awful gas mileage, rich gas fumes, etc.)

have you tried reseting the ECU since you moved? disconnect the battery for a few secs.