Barometric Pressure Sensor Code P0108 not going away :( 1998 Volvo C70 T5

[acfviola]

Hi all,
bit confused about this one,
recently the barometric pressure sensor threw the code P0108 (MAP/Barometric Pressure Sensor Circuit Low.

Thought it would be easy, followed standard procedure and replaced it + cleaned the ever living hell out of it with contact cleaner. Car starts up code is still there, clear it and see if it goes away, comes back in next startup…

what can I do from here?

possibly an electrical or wiring issue?

Car seems to be running a bit richer aswell as I’m km/100L (MPG) has gotten worse… from what I know this sensor being faulty can cause this, or maybe i’m imagining things and my fuel economy has always been terrible.

Either way any advice is greatly appreciated.
Thanks.

[Vova585]

I think it will be best to connect a capable tool able to display reading that ecu is seeing. If on stationary car all looks great- would be nice to have a graff option available and drive around to see if the signal drops. If you see problems right from the start- time to test wiring(if you used oe/oem new sensor and the problem is the same as on old- doubt it is sensor). It should be 3 wire connector. 5v reference, signal and ground. First load test ground with 0.5 amp test light(small bulb, one end to 12v+ another to ground connector through small t-pin). Bright light- ground is ok. Now take voltmeter and test 5v reference. If present- good. Signal wire- remove connectror from ecu and test if short to ground is present(i believe it should be straight wire to the ecu, but best to check a proper diagram)