Noob here. I have been reading from this and other sites for about 2 months now and have gathered some valuable info thus far. I own a 2002 S40 with a 1.9L turbo motor with 120000 miles on it. I bought the car from my daughter so I knew the car for a while. My 16 year old son was needing a car so I bought this from her for him to drive. As soon as I completed the deal I took it straight to a mechanic and had the timing belt,water pump and serpentine belt replaced. Also, it had a miss at idle with a code for cylinder 2 misfire and another for O2 to which he found a coil cracked. He replaced the coil and the 2 plug wires. The car runs and idles very good now.Also during the process of him replacing the timing belt he said everything under the timing cover had a light sheen of oil on it. He said he cleaned everything and ran it for a few minutes to see if he could tell where it was coming from but said he saw no visible leak. I also asked him to do a compression test and any other type he could think of while he had it to see how the motor was performing internally. He said the compression test looked good. After about 2 weeks after my son started driving it we went to check the oil and found oil on top of the motor. We checked it and it appeared low so we added a quart. I told him to check it the next day and he said when he lifted the hood he found the dipstick partially out and raised about an inch from where it should be seated. I immediately thought there must be a PCV problem causing the crankcase to build this much pressure to lift the dipstick so I got to looking online and found that it has an oil or flame trap. I told my son we will need to look into replacing that because it appears it's not doing it's job. I took some wire and wrapped it to his dipstick and tube to keep it from making a mess. After about a month I noticed there was an oil spot in the driveway. I asked him if he had been losing alot of oil and he said yes. I looked under the car motor and everything was covered with oil. I raised the car and cleaned everything as best I could with brake cleaner and cranked the motor and found 2 leaks. One from the oil pan and the other looked as though it was coming from behind the timing cover. I worked on the oil pan and solved that leak but it still has a leak from somewhere on the passenger side of the motor. From what I can tell it only has 3 seals on that side. 2 for the cams and 1 for the crank. The cams look pretty dry so I am leaning towards the crank seal. I also checked out the oil trap to see if there was anything clogged and found nothing. I put it back together and took it back to the mechanic to get his opinion. He first asked what the history was so I explained everything. He said he would start with the engine ventilation system and make 100% sure it was all clear because he took the oil fill cap loose and it appeared to have too much pressure blowing out so I took the car home ordered the parts and replaced the trap and the hose from the trap to the top of the motor. The 2 short hoses were fine but I drained the oil and sprayed brake cleaner in the 2 block holes and hit them with some compressed air to verify they were not clogged. The hose from the trap to the driver side looked fine but I forced compressed air through it to verify it was not clogged. I could hear air going into the block so I figured it was fine. I put everything back together and cranked the car and it still has alot of pressure blowing out when I loosen the oil fill cap. I called the mechanic back and he said the only thing he would be thinking now would be that there is blow by on the rings building up too much pressure for the ventilation system to handle. I just performed a compression test myself and all 4 cylinders are showing 150psi right on the button. All of this to ask if anyone has any suggestions and do they think this motor actually does have blow by. Any info or input would be appreciated and Thanks!!

 

The compression looks good so my first thought is something is still clogged or restricted. If nothing obvious jumps out at you it might be time to take the PCV system apart further and find the restriction.

What worries me more is the oil leak on the timing belt. When mine did that it was the CVVT gear which eventually helped my timing belt slip and bend 8 exhaust valves. The CVVT works with oil pressure directed to it by the CVVT solenoid. Do you think the oil on the timing belt was from the oil on top of the engine leaking or could it be from the CVVT gear (the little plunger looking thing is where mine leaked)?

 

Thanks for the suggestion. I will certainly look into that. I'm also interested in finding out about the hose that comes from the top of the oil trap to the driver side of the motor and where it ends up and it's function if anyone know's.

 

It ends in a banjo bolt on the head. As part of the tear down to replace the bent valves, I had to remove that banjo bolt to remove the head. The opening in the bolt is quite large though. Kinda hard to imagine it clogged up but who knows. If you still have high back pressure and you've checked everything else......

 

Thanks Hudini, I appreciate the input. I talked to a friend who has a friend that owns a shop here in town and one of his specialties is Volvos. I asked him to ask his buddy if he might have some ideas as well. Hope I can get this thing figured out. I may have to bite the bullet and carry it to him. I'm getting tired quick of throwing $ at this car!!

 

Maybe that CCTV gear should be a requirement when changing the timing chain in these vehicles?