Do I need to replace my PCV system?

02V70 · Post by **02V70** » 11 Jul 2023, 17:38

My 2002 V70 has 300k of mostly freeway miles. Im not sure when or if the PCV system has been serviced. I did the glove test, where I put a glove over the oil cap to see if there was pressure. I did not see any smoke coming out of the dipstick or the oil cap, and the glove was being sucked in indicating no (large) problems with the PCV system.

I remember seeing smoke coming out when the oil cap was off before, but I don't remember if the engine was running during that time. I drove the car for about 15 minutes until it warmed up before I did the glove test.

Since the car has 300k miles, should I just replace/service the PCV stuff anyway? If so, what exactly needs to be replaced? Can some components of the PCV system just be cleaned instead?

Post by **Krons** » 11 Jul 2023, 17:50

I have a 02 S60 with 188k, passes the glove test like yours and have no plans to do it until it fails the glove test.

Post by **Blacklab467** » 11 Jul 2023, 21:32

I just did mine for the first time on my 300000km XC 70, it too passed the glove test. I found that components were in good condition without very much residue clogging. The trouble is that you don't really know until you take everything out, and its a fairly expensive job, and not very pleasant to do compared to say front end work, taking a full day. I would say that you cannot clean the component parts adequately and reuse them, and most of the rubber hoses are crumbling at this point in the car's life.
Members on this forum recommend doing a PCV job every 100000 miles I believe. I think this is probably good advise, I took it as an opportunity to change the radiator hoses and thermostat also, and to clean up some of the coil wiring and redo the split loom which had turned into powder on top of the head.
I used the genuine Volvo kit from FCP which included all the hoses including the coolant crossover hose, PCV box, updated banjo bolts ( can save you an engine failure) and bought an oil pan reseal kit which I haven't used yet. Again, rad hoses and thermostat and Volvo blue coolant and a complete flush.
This job cost about $400 and can be completed over 1 day or a weekend if everything goes smoothly and you work slowly. It will give you piece of mind that everything is working as it should and you don't have to worry about blowing seals and running out of oil if its just on the cusp and still passing the glove test. If you have a second car to drive, you may elect to wait until failure.

Post by **abscate** » 14 Jul 2023, 04:49

Ftom your other thread. If you cam seal has blown out you will pass the glove test as it will vent out the cam seal.

Unfortunately you have to replace the seal, then do the glove test to evaluate

02V70 · Post by **02V70** » 26 Jul 2023, 12:28

Cam seals all looked good. If a seal was blown and the PCV was bad, wouldn't there be no suction or positive pressure?

Post by **jonesg** » 26 Jul 2023, 14:37

02V70 wrote: ↑11 Jul 2023, 17:38 . Im not sure when or if the PCV system has been serviced.

since when, how many miles were on it when you acquired it ?

I bought my 04 v70 at 175K miles, cam seals were leaking oil on the timing belt, we changed the seals, they were not blown out, just worn.
I didn't touch the PCV system, 225 miles now and no other problems.
its possible the previous owners did it, I have no idea.
I installed a pressure/vac gauge to keep an eye on boost, it also shows vac , I rarely look at it.
The rubber plumbing under the intake rail really does fall to bits, I found a large vac hose with a large split which I repaired but it will need replacing.

At 300K I would plan to refresh everything unless you can verify it was done.

02V70 · Post by **02V70** » 27 Jul 2023, 12:18

jonesg wrote: ↑26 Jul 2023, 14:37
02V70 wrote: ↑11 Jul 2023, 17:38 . Im not sure when or if the PCV system has been serviced.
since when, how many miles were on it when you acquired it ?

The car has been in the family for the last 10 years ~200k miles. I "acquired it" (could have it if I fixed the head gasket) about 1 year/3k miles ago.

I do plan to replace the PCV eventually but with all the other more urgent issues I have to fix, I'm not sure if I can afford it right now. Does the PCV system suddenly clog up and blow gaskets, or is it slow to fail, and if I do the glove test every month or so, and replace it within 1000 miles of the test failing I would be fine?

Post by **jonesg** » 27 Jul 2023, 18:03

its a crap shoot, but you can only do what you can afford, I'd drive it for now.
at this point you have no symptoms, no sense paying interest on borrowed worries.
A good oil and filter change helps a lot.

hu5ker555 · Post by **hu5ker555** » 28 Jul 2023, 10:21

2008 S60 2.5T 223k miles

Haven't done mine yet, because I know it's a pain. It's not showing any signs of issues, no glove test problems, dipstick stays in place, etc. Runs like a top.

So instead of doing the PCV replacement, I just focus on very frequent oil/filter changes with fully synthetic every time. Every 3-4 months and 3-4K miles. Sometimes I'll also run a little SeaFoam prior to the oil changes if I remember to do so. Hoping all of this proactivity with oil changes buys me more time.