XC70: Engine Advice needed. EGR, boost sensor, MAP sensor all faulty?

[Ajayne]

Hi. I have recently bought a 2011 diesel XC70. It drives well with no issues but after a week the emissions system warning light came on. It's under warranty so I took it to the dealer's preferred garage who replaced the EGR valve. They did say that the old one didn't seem very dirty but they changed it anyway. A couple of days later the light came back on. This time they said that the diagnostics pointed towards the boost sensor. After further investigation they have now decided that it is the MAP sensor that is at fault despite this not coming up initially on the diagnostics. They told me that they tried replacing it with two different generics but neither fixed the issue so they are ordering a Volvo MAP sensor.


To my untrained eye it seems as if they don't really know what is wrong. Has anyone had similar issues who can inform me better about this? If both the EGR and the boost sensor have come up on diagnostics and the MAP sensor is also suspect could there be a wider issue? Have I bought a duff car? It is my first Volvo and, as I said, it drives without any stuttering or acceleration problems as far as I can tell but I would really appreciate any advice so that I can get it sorted properly while still under warranty.


Thanks for reading.

Amanda

[V70Zig]

Well, from what I've just read......I take it you bought it from the main dealer? And I'm assuming that the "preferred" garage is local to you?

Your "preferred" garage might not be up to it...only a guess....

My advice.....Ring the main dealer you bought it from, tell them what has happened and what the preferred garage has done, if they are not close to you then tell them that you expect a courtesy car while they sort it out....

[AndyV7o]

Map sensor is the boost sensor. Mass Air Pressure = MAP
Thet might mean the vacuum solenoid which diverts vacuum from engine mounts to boost solenoid when they say boost sensor...
Id have though emissions warning coukd relate to dpf and/or its related sensors rather than intake related items such as map/boost solenoid?

[Clan]

Originally Posted by AndyV7o

Map sensor is the boost sensor. Mass Air Pressure = MAP
Thet might mean the vacuum solenoid which diverts vacuum from engine mounts to boost solenoid when they say boost sensor...
Id have though emissions warning coukd relate to dpf and/or its related sensors rather than intake related items such as map/boost solenoid?

There are three ambient air pressure sensors on the car , the one that can go faulty is the one in the intercooler outlet stub , It really is best it goes to the dealer who has experience and knowledge .. EGR Valves on D5 are very reliable and robust .

[Ajayne]

Thank you for clarifying that for me. I bought the car from a private dealer 40 miles away so the garage that is handling it is the dealers choice under the terms of the warranty. The garage is working for him not me. I have a basic OBD2 scanner which gave the reading as an EGR fault (p1407). Initially the garage seemed to agree with this and changed the EGR valve although that made no difference and now the issue seems to have gone deeper. I'm worried that there could be a bigger issue with the turbo system although the car seems to handle well. I will mention the intercooler outlet stub sensor to them, I really have no idea about the garage's expertise with Volvos If it's not fixed this time I could take it to a Volvo specialist but that will probably be at my expense.

[Zebster]

Originally Posted by AndyV7o

Map sensor is the boost sensor. Mass Air Pressure = MAP
Thet might mean the vacuum solenoid which diverts vacuum from engine mounts to boost solenoid when they say boost sensor...
Id have though emissions warning coukd relate to dpf and/or its related sensors rather than intake related items such as map/boost solenoid?

You are mixing up MAF (Mass Air Flow) and MAP (Manifold Absolute Pressure).

MAP, with the engine off, will usually give a live reading of around 1 bar (100kPa) on a suitable OBD2 reader. And that's a good way to test that sensor!

[AndyV7o]

Indeed! Lol! I knew what I meant
Still, though I used the wrong words, its still reading air pressure 👍
You can blame the kids and wife for that. Plus the heat. Ive been on another planet...

[V70Zig]

Originally Posted by Ajayne

Thank you for clarifying that for me. I bought the car from a private dealer 40 miles away so the garage that is handling it is the dealers choice under the terms of the warranty. The garage is working for him not me. I have a basic OBD2 scanner which gave the reading as an EGR fault (p1407). Initially the garage seemed to agree with this and changed the EGR valve although that made no difference and now the issue seems to have gone deeper. I'm worried that there could be a bigger issue with the turbo system although the car seems to handle well. I will mention the intercooler outlet stub sensor to them, I really have no idea about the garage's expertise with Volvos If it's not fixed this time I could take it to a Volvo specialist but that will probably be at my expense.

Might be worth a shout out for a member near you that has Vida Dice to read specific volvo codes then. The preferred garage may not have the diagnostics that can read them. Good luck.....

[Clan]

Originally Posted by Ajayne

Thank you for clarifying that for me. I bought the car from a private dealer 40 miles away so the garage that is handling it is the dealers choice under the terms of the warranty. The garage is working for him not me. I have a basic OBD2 scanner which gave the reading as an EGR fault (p1407). Initially the garage seemed to agree with this and changed the EGR valve although that made no difference and now the issue seems to have gone deeper. I'm worried that there could be a bigger issue with the turbo system although the car seems to handle well. I will mention the intercooler outlet stub sensor to them, I really have no idea about the garage's expertise with Volvos If it's not fixed this time I could take it to a Volvo specialist but that will probably be at my expense.

your contract is with the dealer who sold you the car , take it back and leave it with him to sort out .. that is the way to handle the problem

[Peter86]

Worth getting the main dealer to sort the car while in warranty. Its amazing how much stuff is connected on a car in one way or another. Good diagnostics helps a lot in problem finding.