Hi guys,
just bought an s40, 2008, 1.6 petrol. Two days ago, before buying it, I took the car to a Volvo center to check the codes and everything was just fine.

Today I get these faults at once:
1. Fault in car's emissions system.
2. Low oil pressure.

This is my first volvo and I saw these problems are common. But I am wondering why both these 2 errors occurred after checking the error codes.
If you know, give me some insight please! Thanks a lot!

 

Need some more information. If you have a 1.6 S40 then it is not a US vehicle. The oil pressure is used to drive a number of components that could affect emissions so they may be related. Have you check the oil level in the engine?

 

Hi scotsborn! Yes, I'm from Europe. I checked the oil level this morning and is almost to the max, so that's fine. To mention, after I checked it both lights disappeared fron the panel, but came back on after a half an hour of driving.
Could be the sensors problem?
Also I am nearly.the limit of changing the oil and filters. Could that resolve the problem?
Thanks! Cheers!

 

Are you getting a whistling noise from the dipstick tube? You may have a clogged PCV system. There is a recall on certain US models for this system. It's the metal unit that holds the oil filter on the front of the engine.

 

Hi Hudini, there is no noise. If I have a clogged PCV system, wouldn't that appear when they checked the car for error codes at the service?

 

No error codes from this problem as there is no sensor. I was just giving suggestions.

Low oil pressure: first check the oil level. Too much or too little. The oil level on this engine is checked best after it sits overnight. If you check the level immediately after running the engine you will overfill it because the oil in the filter drains back to the pan after 10 to 15 minutes. Too full causes the oil to be whipped into a froth by the crank. This introduces air into the oil system. Of course, too little does the same thing.

Next try some heavier weight oil. 10W-40 or 20W-50 to see if this makes a difference. The heavy oil will raise pressure. You want to see if anything changes.

If nothing changes then check the pressure. I would hook a mechanical guage to the engine but not everyone has access to a guage. In this case you might consider a new sensor.

If nothing above helps then you may have a worn out pump. I have seen on the older Volvo 240 the overpressure spring hang open causing low pressure. This is not an easy fix though.

 

To add to Houdini's comment - when you change the oil also use an OEM quality filter (ie Mann). Not all replacement brands are properly sized for flow (particularly those that advertise "double filter action" or something similar) which can contribute to low oil pressure.

 

Thanks guys,
The oil level is almost to thr max, checking daily. I noticed an increase in fuel consumption. What is the relation between consumption increase and low oil pressure?

 

I sure hope there is no relation. The emission system fault can be as simple as leaving the fuel cap loose or more complicated with a vacuum pump failure. Which exact code did you get?

Are you getting the red oil can symbol on the dash for the low oil pressure? Does it happen on start up or after the engine is hot?

 

I am getting both symbols - Emissions and Low oil pressure. But I get them only in key postion II. When I start the engine they disappear.

 

Been to the service, everything is fine!
Thanks Hudini, scotsborn and mt6127 for your replies!