Physical location of a MAP sensor - 1994 850

gyuri · Post by **gyuri** » 26 Jan 2012, 09:17

The on-board diagnostic indicate a MAP sensor problem. The car either does not start or idles very low and rough and eventually dies.

I can not find the MAP sensor in my car. None of the documents I used gives the actual location or any suggestion toward the resolution of the problem. Help would be greatly appreciated for I've been looking for this item a long time. Thanks for your assistance.

Post by **jblackburn** » 26 Jan 2012, 09:41

On the earlier models (850's) the MAP sensor is located next to the cooling fan relay and yes there is a vacuum hose between the sensor and vacuum tree near the throttle body.

Look at the cooling fan shroud right above the fan and you'll see a big grey relay. Should be next to that.

Post by **3903davis** » 26 Jan 2012, 14:01

I thought it was located in the lid of the intake over the air filter box. cable loom plugged into it. could be the plug is not plugged in well.

Post by **jblackburn** » 26 Jan 2012, 14:03

If the OP is talking about the MAP (essentially a barometric pressure sensor) sensor (not the MAF - airflow) sensor, then this is the correct location.

It moved to near the windshield washer tank on the 1998 models.

Post by **jimmy57** » 26 Jan 2012, 14:46

Bosch fuel systems did not use MAP sensor. Some used a barometric pressure sensor that was only an input as a reference sensor for fuel tank pressure testing. If the altitude is high the test is not required by EPA rules and is not performed. Baro sensor has no impact on the way the vehicle runs.
I would make sure the code wasn't for MAF sensor.

gyuri · Post by **gyuri** » 26 Jan 2012, 15:03

Thank you all for the response. I am beggining to think that jimmy57 has the correct solution since I looked high and low for a long, long time without finding any part even remotely resembling the illustration I have for this part. The on-board diagnostic gave me the code "1-2-1" which is shown as a problem with the MAP sensor. The problem of very low RPM and dying and/or start but quick dying is still rendering my car undriveable.

Post by **osman** » 29 Jan 2012, 19:22

unplug the MAF,if the idle improves slightly its bad.
If it runs the same, the problem remains elsewhere.

Post by **jimmy57** » 30 Jan 2012, 04:54

850's built for the US market never had MAP sensor. A few for Canada with a 10 valve engine did have MAP. I'm betting you didn't manage to get an illegal car with a lower powered engine into the US.
The MAP sensor on 99-2000 S70 and V70 is on radiator top shroud.

The BARO sensor would not have a hose on it as its reference is atmospheric air pressure.