PCV valve question

hello,

2002 honda accord SE 4Cyl about 110K on car.

My mechanic says PCV valve is jammed and needs to be changed. I changed the
value 7-8 months ago (about 10K kms). What could cause the valve to jam so
fast. The car does idle rough. I just change my spark plugs. Is there
anything else I should be checking

Thanks in advance for advice

 

If you used an aftermarket valve it was probably pretty bad when you got it.
If it was a Honda PCV valve, that would be unusual.

Mike

 

"Jammed" or plugged with sludge?

If it's "jammed" it's an aftermarket piece of crap. Replace with OEM.

If it's plugged with sludge, then the car has been the victim of very bad
maintenance and you have other, more serious problems than a plugged PCV
valve.

 

I had replace it with an OEM valve bought from a honda dealership. The car
has been always serviced at a honda dealership as I had 7 years 130K
extended honda warranty. The warranty ran out Nov 2008 and then I started
going to a local guy for oil changes and used synthetic oil (5w20).

When you say serious problems what could that be?

markov

 

Oil in the throttle body, mostly. That's often (but not always) symptomatic
of deep trouble in the engine.

How does your guy know the valve was "jammed" in the first place? Did your
guy find oil in the throttle body?

Even if the valve was "jammed", this in itself would have had little
material effect on the engine's behavior, since vapors would just enter the
intake through the open breather pipe (the other side of the PCV system).

 

Then what would be the reason for rough idle? I have replace the spark
plugs.

 

That would depend on whether it is jammed closed or jammed open. If open, it
is a pretty big vacuum leak.

Mike

 

For which the ECU/ECM/PCM completely compensates.

Air leaks into a feedback system are not the problem they were in non-
feedback systems until they exceed the system's ability to adjust.

You'll notice that if you perform the approved diagnostic on the PCV valve
(pinching its hose shut), the idle will drop, then _recover_.

 

There are a hundred possible reasons for rough idle. This can ONLY be
properly diagnosed with hands-on investigation that covers everything from
cylinder compression to engine mount integrity to consistency of spark to
cleanliness of the intake system, to who knows what.

I gave up long ago trying to give remote help to people with rough idle
problems because in the end I was usually wrong.

 

Re the PCV valve--

We have had this discussion before and I am happy to continue to agree
to disagree. I would just note that many authoritative sites say that
fuel mileage may worsen with a malfunctioning PCV valve. The
interested reader should google.