2008 XC90 3.2L with codes P0171 and P0174 - Help
 

Hey guys,

I have a 2008 XC90 3.2 AWD with 75,000 KMS that I got recently.

Checking with OBD FUSION, I got the codes:

P0171 and P0174 System Too Lean
P0507 Idle Air Control RPM Higher than expected.

The car feels and drives normal but I want to fix these before it gets worse.

Searching on the web for these codes P0171 and P0174 its look like maybe the problem is the PCV but I don’t find any info, pics or DIY fix for this issue on a 3.2L engine

Have any of you with 3.2L engine has experienced these same codes?

I going to check if I have a vacuum hose leak but can you advise were I need specially to look

Thank you for your time and help

Isaac


Attachment 15382

Hey Guys

After several web searches, I found that these two codes are related to the PCV OIL TRAP – VALVE COVER.

Since the membrane/diaphragm is damage, it alow air to enter in the system that the MAF is not metering and that why it trow System Too Lean codes.

This is causing a small misfire and I am pretty sure is consuming more fuel.

So today I was checking the black housing on top of cylinder head and the first thing I notice is that is all covered in oil.

Also notice a hissing noise that is coming from the engine oil cap. I removed the oil cap and put my hand over the hole and there is a "noticeable" suction.

I am thinking in ordering:
PCV OIL TRAP – VALVE COVER Part No. 31319642
VALVE COVER GASKET Part No. 30731243

Can you guys, let me know what’s the correct torque setting for the torx screws for the PCV OIL TRAP VALVE COVER?

Thx for your time and help

Isaac
Attachment 15355

So today I have more time to check the valve cover Oil Trap and in the name of the science, research and investigation :-) I decide to remove the plastic cap on top of the diaphragm housing.

I know other brands like VW and BMW sell the membrane/diaphragm alone so I was expecting to see if I can replace it and save some $$$

I went to a place where they sell OEM and aftermarket parts for BMW. They were very similar but none of them fit or was the same.

On the Volvo membrane/diaphragm there is a part No. CF W 3A MB66-24

Doing a search on the net I don’t find anything under that part No. or something similar.

Anybody knows where can I get this part? If not, I will have to buy the complete valve cover oil trap :-(

THX,

Isaac

Attachment 15348
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Attachment 15351
Attachment 15352Attachment 15353 Attachment 15354

You have to buy the whole thing

Hey Guys.

So yesterday, I change the PCV OIL TRAP – VALVE COVER Part No. 31319642 on my 3.2L and cleared/reset the P0171 and P0174 System Too Lean codes and now the engine is smooth and not misfires.

So today I was driving and my check engine light come on and these are the codes I get:
P0172 and P0175 System too Rich.

Any advice what to check? Or what other test to make with the OBD Scanner?

THX,

Isaac

Here is the screen shot of the OBD Codes and also the Term Fuel % on idle on Bank 1 & 2

Attachment 15314

Attachment 15315

I forgot to update this topic

After using the car for around 3 weeks, the Engine Check Light turn off by itself.

Engine is smooth as silk ;)

Hope this info help others

THX,

Isaac

Diaphragm for PCV oil trap cover volvo XC90, 2007, 3.2 L
 

You can purchase this diaphragm separately from www.vanos-bmw.com.

The price is 19.90 USD.

It works perfectly.

Valve Diaphragm Found
 

This is an old post, but it took me ages to find one of these online, so I thought there might be others out there with the same problem.
I found one listed as: "Membrane oil trap VOLVO engine 3.2L engine B6324S Si6" on Ebay: https://www.ebay.com/itm/Membrane-oi...-/172267660060
Saved me roughly $400 (Australian).

Also, the codes reset and the ECU remaps after disconnecting the battery and draining residual power in the system (e.g. turn on and hold ignition key for 5 seconds or so).

https://i.ebayimg.com/images/g/oKYAA...Qrn/s-l500.jpg

Codes P0171 and P0174, different problem
 

Hey folks, I thought I would post this since I just learned these codes can be set with a different problem. They came up on my 2007 about a month ago so I ordered and changed the oil baffle to no avail. Codes kept coming back. Took it to my local shop with better scan equipment and come to find out the injector O-rings are leaking. Makes sense to me since I also just recently changed the fuel pressure sensor and pulled the injectors and rail to get at the sensor. Local guys wanted $780.00 to pull the injectors and replace the O-rings. I said no thanks, ordered the O-ring kits from the Volvo Web parts store, $10.45ea plus $4.50 for a new fuel rail O-ring and will pull the injectors myself, send them off to Injector Rx in Texas and have them cleaned, new O-rings installed and tested for $18.00 each. These guys did the injectors for my 2001 Jaguar XJR and it made a big difference.


I'll post again after reinstall and let everyone know how it goes.

Hey Linestarboard,

Thank you for this info.

When I was fixing my problem, I was looking for the Membrane only, but never find it. :mad:

THX & Happy New Year

Isaac

Hi guys,
My 2006 XC90 V8 has been showing fault code P0193 (pressure sensor) on and off for a few weeks but I have not noticed any drivability change or fuel economy change. Now it started showing fault code P0174 (lean condition detected Bank 2) also but continues driving OK. Has anyone had these problems?

I am asking for an answer (p0174)
 

Did a new injector seal help? Did this fix the p0174 problem?

Thanks
Jan