1998 S70 P0108 and P0325

[deepsouth]

Hey all--
I have a 1998 S70 2.4 Turbo that just threw a P0108 and a P0325. I understand the p0108 is a map sensor and I think I found it (see photo below). For some reason the Haynes manual shows the MAP sensor as the air pump solenoid under the radiator shroud (I performed the SAS delete and removed everything but that solenoid hundreds of miles ago, so I know that's not the MAP sensor).

And p0325 is a knock sensor/s issue (which I believe I need to remove the intake manifold to replace?).

So, here's what I'm wondering:

Can these two codes be related?
Can I test the MAP/Altitude sensor?
Can I test the knock sensors (preferably without pulling the manifold)?

Thanks for any all help!!!!
Eric

[Ozark Lee]

The '98 really doesn't have a MAP sensor but an altitude (barometric pressure) sensor that throws the same code. The code is for an open circuit so I would first suspect a bad electrical connection.

Where did the sensor you have pictured come from? The baro sensor is mounted just inboard of the windshield washer fluid bottle if memory serves correctly. I've never had to mess with one so I don't know if what you have pictured is the correct part or not.

The knock sensor is a glorified microphone and they really aren't prone to going bad. I'm not sure of a resistance specification but I would think about any resistance would mean they are OK. If I can get to the box in the garage I have a set and I will take a resistance reading on them.

I suppose that if the Baro sensor or the connection to it was bad the ECU could make some bad fuel mixture decisions and cause knocking.

...Lee

[deepsouth]

Yes, this came from just behind the windshield fluid filler (mounted to the fender). I took it off, cleaned the electrical contacts, and put heat shrink on cracked wires and the p0108 code seems to have cleared. The knock sensor code, however, keeps coming back. I've never replaced a knock sensor on a volvo but I believe I have to pull the intake manifold off? Is there anything else a code p0325 could be?
Thanks!
Eric

[Ozark Lee]

The intake manifold does need to come off but once it is off they are very easy to change. The torque spec is critical as is the orientation of the sensor. I can't think of anything else that would be unrelated and throw the code other than another bad connection at the socket. By the '98 model year both sensors should go to a single connector down by the starter - conveniently located to catch the maximum amount of crap off of the road.

...Lee