[5-cylinder D4] is the boost pressure sensor broken?

[flanker711]

Hi Volvo bros:

I have a MY2012 5-cylinder V60 D4 1984cc FWD. Current milleage is ~120000KM.

The emission check light turned on two weeks ago. But there's no warning message shown up on the console,

I used Car Scanner App and a ODB2 bluetooth dangle to read out the error codes. There're two errors:
- P0073 Ambient Air Temperature out of range (reading is -40). This should be due to a recent incident damaging the left mirror housing.
- P1407 EGR no flow detected.

The non-continuous sensor has an error:
EGR Monitor Bank 1 MID$31 TID$90 Failed. Its values is 100.0064%, while the good range is 0%-90%.

Searching through the Internet, it seems likely to be a problem related to boost pressure sensor (near the intercooler).

I don't have a VIDA DICE for more professional diagnosis. As it seems not be a critical problem, I just want to get some data from ODB2 for more analysis.

So far the following groups parameters are monitored:
1) EGR command. EGR position sensor, EGR error.
2) DPF soot, DPF temperature, DPF pressure.
3) MAP, baro pressure, boost pressure sensor, boot pressure sensor desired value.

screenshots attached:

EGR parameters seem ok. EGR command changes regularly and EGR position adapts accordingly, EGR error is always small.
DPF parameters look ok too. There's soot burning when temperature is high enough. But DPF pressure always become 255hpa when engine is stopped by start-stop.

What puzzles me is the pressure related readings. At my location, baro pressure reading is about 96kpa.
- At 0 rpm: MAP 95kpa, boost pressure desired 109.1kpa, boost pressure 111kpa
- At idle: MAP 95kpa, boost pressure desired 103.1kpa, boost pressure 110.2kpa
- At crusing: MAP 129kpa, boost pressure desired 126.5kpa, boost pressure 152.4kpa

It seems boost pressure reading is always higher than MAP/desired. The error is higher when pressure is higher.

And in my understanding, MAP value should be close to boost pressure desired and boost pressure in steady state. (Could someone confirm on this?)

If this OBD2 reading is trustful, can it be conclused the boost pressure sensor is faulty (reading too high)

Thanks in advance!

Felix

[piotrek]

I think your conclusion is correct: boost pressure sensor is reading too high.

I my 5-cylinder D4 1984cc FWD engine boost pressure always follows the desired boost/MAP, always with a slight delay. Boost pressure will never be higher than desired boost (except for a split second when I let off the throttle - then desired boost is momentarily lower than boost pressure, due to the same slight delay as when accelerating).

My values: ignition on, idle, accelerating, screens in Car Scanner ELM OBD2.

I also get DPF pressure 255hpa with engine off, seems normal (last screen).

[flanker711]

Thanks piotrek! Your screenshots are really good references!

I will try cleaning / replacing the boost pressure sensor.

Originally Posted by piotrek

I think your conclusion is correct: boost pressure sensor is reading too high.

I my 5-cylinder D4 1984cc FWD engine boost pressure always follows the desired boost/MAP, always with a slight delay. Boost pressure will never be higher than desired boost (except for a split second when I let off the throttle - then desired boost is momentarily lower than boost pressure, due to the same slight delay as when accelerating).

My values: ignition on, idle, accelerating, screens in Car Scanner ELM OBD2.

I also get DPF pressure 255hpa with engine off, seems normal (last screen).

[barry4913]

Hi

I have a 2012 V60 with only 39,000 miles on. Fault codes P023400 and P140700 showing. Indicated EGR valve issues but I believe its more likely a sensor fault. I've cleaned the MAP Sensor at the front of the engine which was badly sooted up and the Engine light stayed off for 2 weeks. However it has reappeared and I want to check the Boost Pressure sensor switch as you mention but I cant locate it. Could either of you give me some directions Please.

Thanks.

Barry

[Mad Mark]

Hi did you find the boost sensor , if not you can see it on the right hand side below the light on the edge of intercooler , tight to get out if you have big hands

[Mad Mark]

Did a new boost sensor cure the problem please ?

[pacmyc]

I'd wonder as well.. I have the same problem and it would be really nice to know your outcome of the problem.. Also, can you replace it from top or from below? I looked in Vida, and it seems volvo recommends removing the cooler in order to access it..