When to replace a PCV valve, Toyota 2AZ-FE

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Short version:
Is there a benefit of changing the PCV valve early (40,000 miles) in the 2AZ-FE Toyota engine that currently has no oil consumption issues?


Long version:

So the Scion xB in my sig has the 2.4 L 2AZ-FE 4 cylinder that has known oil consumption issues (has a TSB for excessive consumption).
Mine has no issues at this time and I want to do what I can to keep it from happening.
From my understanding, it is due to a piston/ring oiling design flaw allowing the oil passages in the piston to the rings to get clogged up.
I have heard conflicting info on if the issue was fixed by the time my engine was made (late 2012), or if mine is even covered in the TSB for it.
I only have ~38,000 miles on the engine now, and as said have no consumption issues at the moment.
The issue tends to start showing up as early as 45,000 miles, but usually around 60,000 miles.

Car is mostly shorter trips (5-15 miles) around town, with at least monthly trips to family 50 miles each way, all highway.
Maybe once a year a 450 mile each way visit to other family.

First 5 oil changes (4,903, 9,728, 13,491, 16,598, 19,859 miles) were done at the Toyota dealer using TGMO (5w-20) and Toyota OEM filters.
I am now doing a 5,000 mile OCI (6-8 months now that the wife is not working) with xw-20 synthetic oil.
Pennzoil Platinum 2 previous changes, Auto Zone Syn right now. Oil stash includes 2 changes of QSUD, 1 change of M1 EP, and finally 6 changes worth of Magnatec.
I am using/will use Wix,Bosch D+ from my stash, then probably Fram TG filters (XG not worth it for shorter interval, but if I did, I would leave filter on for 2 oil changes).
Hopefully the shorter OCI with synthetics will help combat the problem, but I want to do all I can to help prevent the issue from showing up.

So this is where the question actually comes up.
Will doing a preventative PCV valve replacement at say, 40,000 miles help any at all?
It is like $8 on Amazon for an OEM valve, and is super easy to replace.
I know the PCV valve is not a cause for the issue, but if it is something that may help, why not, right?
 
Umm sure. If it's cheap and easy do it. Most people have no idea what's going on or don't mention anything to a tech and pcv has been bad and burning oil away forever. So I say replace it good preventive maintenance.
 
Don't bother .just make sure the wire from battery to starter alternator ground are more away from engine .and try to only put 0% ethanol gas if possible. By air gaping wire and gas with 0% ethanol you should prevent issue from popping up . Yes you could airgap all wire almost touching engine but it's a drag . And finding pine cone tywrap holder that are 5 millimeter away from the engine is likely only avail online.yes manufacturer should install all wire the airga way .why they don't ? They probably don't know that electromagnetic field and electric field are two problem
 
With a known issue clogging small oil passages, I'd be using a synthetic oil known for good cleaning ability: M1. Amsoil is less well known but also keeps things clean.
 
Run 4oz of Marvel Mystery Oil per every 10 gallons of gas (per the label on the bottle) to keep the piston drainback holes clean.

Hey, it can't hurt - and I have seen first hand how nice piston skirts look when running the stuff in the gas. (I don't recommend putting it in the oil)
 
It wont prevent oil consumption issues. If your car starts using oil and if the cause is the PCV then replacing it will stop the consumption issue. However, a new PCV is cheap enough. I changed mine once and likely wont bother again unless I notice any consumption. I wouldnt change it for nothing. Its a good 1st step if you start noticing consumption.

Oh and using non ethanol gas or MMO wont change anything besides cost you money.
 
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I check mine yearly and it would be the first thing I would check if I noticed oil consumption and didn't find an external leak. Basically it is a one way valve. Air is supposed to flow one way and not the other. It is supposed to rattle freely when shaken. I spray with carburetor cleaner to clean and replace. Never had one fail in the vehicles I have owned.

I have seen people complain about aftermarket PCV failing. $8 is pretty inexpensive for an OEM PCV, if it gives you peace of mind. Just make certain it is a genuine OEM part.
 
2AZ-FE had a problem with weak rings, right? Nothing will fix that issue, quality oil, gas, whatever. If the ring gives up due to being poor metal, then nothing in a can could fix it.

Now clogged drain holes would be a different story. Quality oil might stave off the issue.
 
Originally Posted By: yvon_la
Don't bother .just make sure the wire from battery to starter alternator ground are more away from engine .and try to only put 0% ethanol gas if possible. By air gaping wire and gas with 0% ethanol you should prevent issue from popping up . Yes you could airgap all wire almost touching engine but it's a drag . And finding pine cone tywrap holder that are 5 millimeter away from the engine is likely only avail online.yes manufacturer should install all wire the airga way .why they don't ? They probably don't know that electromagnetic field and electric field are two problem


Nice try.
 
The 2012s have oil burning issues, too? I thought it was limited to the 07-09 model years. I know my 08 tC with the 2AZ-FE burned about a quart every 2-3k or so.
 
Apparently the TSB has been expanded to pretty much all 2AZ-FE motors (at least that is what someone here had posted).

I just want to do what I can to stave this off if possible.
This car will become my daughters in 2 years when she turns 16 and will probably get her through college and then some.
Although I am teaching her to check oil regularly even before she starts driving, it would be one less thing to worry about.

My truck uses about 1 qt every 1500 miles, but it has a 6 qt capacity, so running a qt low on that is not quite as bad as a qt low on a 4 qt sump.
 
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