Motor Vehicle Maintenance & Repair Stack Exchange
Motor Vehicle Maintenance & Repair Stack Exchange

Questions tagged [pcv-valve]

PCV is and acronym for Positive Crankcase Ventilation. It is part of a system that helps control air pollution by burning fumes that collect in the engine crankcase instead of venting them to the atmosphere.

40 questions
11
votes
8 answers

Is the vent from the pcv valve back into the air intake really needed?

After working on my car, I didn't bother to reattached the line from the pcv valve into the air intake before testing the motor. It ran normally. This made me question whether I need to even return it into the air intake. Basically, can I run the…
Wulfhart
  • 705
  • 2
  • 6
  • 11
8
votes
3 answers

Oil in air intake: is this a faulty breather valve or by design?

I noticed the other day that a component (breather valve) was not fitted properly (the clip that held the valve cover breather in place was sitting between the O-ring and the lip, instead of fastening the component to the top of the engine) and…
sebf
  • 245
  • 2
  • 4
  • 6
5
votes
2 answers

Smoke coming out of oil fill port

I've been reading up on this smoking oil dipstick tube/oil port for Volvos and they all seem to stem around a clogged PCV system as being the root cause. We're looking at a 2005 Volvo S80 5cyl 2.5L Turbo engine with about 85K miles on it. When I…
jxramos
  • 1,880
  • 10
  • 34
  • 49
5
votes
1 answer

Planning to fit an oil catch can into my car. Any problems with this setup?

I own a 2007 Ford Fiesta ST150, I have modified it a little, one of the mods is a cold air intake. I want to install an oil catch can setup, but as the PCV vent is behind the intake manifold and requires the entire manifold to be removed to access…
WeakMech
  • 964
  • 3
  • 11
  • 22
5
votes
1 answer

2001 Mercury Sable -- Rough Idle/High RPM and Transmission Leaks

I have a 2001 Mercury Sable (24V DOHC V6) that has been having problems with its vacuum system. I live in Florida where the average temperature lately has been in the 80s. I've been experiencing a very rough idle for roughly a month now that…
Sage
  • 291
  • 1
  • 3
  • 10
4
votes
1 answer

Toyota auris 2010 stalls when you remove oil cap while engine is idling

I was inspecting a used Toyota Auris (2009-2010). I turned the engine on and with the car idling I removed the oil cap from the engine. The car stalled within seconds and the engine almost shut down. I have read several websites. Half of the people…
Leo
  • 41
  • 1
4
votes
1 answer

How to diagnose a vacuum hose leak or pcv pump problem

I have a old 1993 Mitsubishi Triton MJ which is having a bit of an issue at the moment with acceleration. With the initial acceleration such as moving away from traffic lights the engine will often sputter and struggle and almost stall. From my…
Tim
  • 465
  • 2
  • 8
  • 17
3
votes
3 answers

Does checking for air coming from the oil fill hole tell you that the engine is bad?

This video suggests removing the oil cap when the engine is running and checking for the amount of air that is coming from the oil fill hole. (They call this air "blow-by".) He says that if the air is strong, that might mean that the engine is…
Utku
  • 285
  • 1
  • 5
  • 13
3
votes
2 answers

Replacement PCV valve unavailable. Will any other do?

1979 Leyland Sherpa 230 petrol 1.7l with "O series" engine I have an "oil separator" (or oil catch can) attached to the side of my engine. From there it goes through a hose to the ported vacuum by the throttle plate of an SU carb. Inside the hose is…
Michael Sherpa
  • 258
  • 4
  • 14
3
votes
1 answer

In the PCV system, is an "Oil Trap" the same thing as a "Breather Box"?

I've seen images of something labeled as an oil trap that looks like a box shaped part. In another context, I hear people talking about breather boxes. It sounds like they're talking about the same part, just with some synonymous terminology. Are…
jxramos
  • 1,880
  • 10
  • 34
  • 49
3
votes
0 answers

high oil consumption and oil pressure, possible PCV system malfunction

I have a 1993 C1500 4.3L manual transmission. My oil pressure has been reading very high (fluctuates, but generally goes beyond the upper range of the gauge). I had the truck in the shop and the mechanic indicated the intake was gummed up because…
derelict
  • 283
  • 1
  • 10
3
votes
1 answer

Where is the PCV valve on my 2011 Ford Focus SES (Duratec engine)?

I have a 2011 Ford Focus SES with a 2.0 liter I4 Duratec PZEV (California edition) engine. My repair manual suggests replacing the PCV valve every 60k miles (I am currently at 75k). I am trying to find the PCV valve but am not sure where it…
Jeremy White
  • 288
  • 3
  • 12
3
votes
1 answer

Testing PCV: Constanct Suction or Pulsing Suction

I tested my PCV by taking off the oil fill cap and placing a piece of paper over it. I observed a pulsating suction and not a constant suction. Is that normal? If it's normal should I clean the PCV anyways since it's probably never been cleaned…
Robert S. Barnes
  • 15,780
  • 72
  • 157
  • 249
2
votes
0 answers

Smoking XC90 after PCV box replacement

I have a 2003 Volvo XC90 2.9L T6 AWD and for the most part, it’s been great. Over the past year or so I’ve had an issue with it randomly stalling at slow speeds which was progressively getting more frequent. Along with this it did start to hesitate…
Richard KeMiKaL GeNeRaL Denton
  • 121
  • 1
2
votes
0 answers

Tracking Down Excess Crankcase Pressure

So a problem I've been putting off dealing with for a long time is the excess crankcase pressure in my 99 Nissan Almera 1.6L. You can see here in the air box the results of this excess pressure: Blow by and crank case vapors are obviously being…
Robert S. Barnes
  • 15,780
  • 72
  • 157
  • 249
1
2 3