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Old 11-06-2014, 04:39 PM   #1
Duvanator
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Default Variable Valve Lift Oil Pressure Switch Failure (w/ information)

Below is a picture of the pressure switch, it is on 2006+ 2.5i engines (not to be confused as being variable valve timing). There are two of these on the engine, one on each head. On the driver side it is located right at the front of the head, on the passenger side it is located on the back of the head closest to the firewall.


Driver side:

(stolen interwebs picture)


onto long background story:

My car has about 135,000km on it now. At about 125-130000 I started to notice an oil drip on my driveway, I though it was a lose/weeping oil filter so I tightened it up a little and went on my way. A few days go by and the drip is still there, this makes me concerned and I get the car up on a hoist to inspect whats going on. As it's in the air I see oil all on and around the bottom of the passenger side head, first instinct was O KNOW headgasket failure!, then upon closer inspection the majority of the oil was closest to the valve cover, so I continue to inspect. It turns out the oil was coming from the top of the head and running down.

Then I noticed the VVL oil pressure switch, it was covered in oil, I cleaned it up and drove the car and sure enough it was weeping oil again. It appeared to be weeping out from the top AND the mating surface between the aluminum bottom and the plastic top of the sensor. (in the picture you can see the white plastic which the connector clips to, and the grey underneath which the sensor itself, and then the threaded aluminum base)

Ok, so I've found the culprit, I order the switch and swap it out, problem solved. Didn't think into it any more, until yesterday...

Yesterday I'm driving to work and I smell burning oil, I don't think anything of it because I've had zero issues with my car and figured it was the old ford pickup in front of me. Driving home from work I smell it again at a stop light, but this time I see smoke coming from the front of my hood, UH-OH!

I pull over open the hood and a plume of white smoke (this cant be good), I see the under-tray at the front of the engine is wet with oil, the valve cover seal along the front is wet with oil, I follow it up, and behold its now the driver side VVL oil pressure switch which is soaked with oil. MUCH MUCH worse than the passenger side one when this happened. I checked the oil and I'm down about 1/2 quart. I cleaned up the area last night, topped up the oil, ordered a new switch and plan to install it today after work. When I arrived at work I checked the switch and sure enough its wet with oil again.



/end of long background story.






Point of this post/ question:

Has anyone else had this issue? had even just one of these switches fail on you? or both? or am I just unlucky and have a batch batch of switches installed from factory?

Is it just the inherent bad design of the plastic and aluminum melded together being constantly heat cycled on the head?

Both failed within about 5000 km of each other, coincidence?

I don't have an oil pressure gauge, but is this a possible result of to high of oil pressure?









(I posted this on torontosubaruclub.com forums and wanted to post it here to as through my research I have found this to be a common issue.

I have found this relevant information thus far:
- This is a somewhat common problem, and sometimes the pressure switches are known to leak profusely

- The P0026 and P0028 are related to the VVL. Basically they are indicating that when the VVL control system is calling for high pressure, the pressure sensors aren't seeing it, and vice-versa. That could be caused by faulty oil switching solenoids, but it could also be caused by faulty sensors.

- If one of the above codes is evident start by replacing engine oil filter with an OEM filter as this has resolved the issue for some.
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Old 11-07-2014, 09:34 AM   #2
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FWIW, I had a ~95ish GMC Sonoma. One day I go to drive the truck and I see my driver side mirror laying on the ground. I looked around, and wondered if someone knocked it off deliberately. Replaced it, and moved on.

Like a week or two later, I'm driving on freeway and the passenger side mirror falls off while driving. I was relieved to know it wasn't vandalism the first time, and LOL'd at the close proximity of failure between the two.

I don't know anything about your specific issue, but related things can fail in close succession.
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Old 11-07-2014, 11:02 AM   #3
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I had something similar. It started with a p0028 or 26 code (what ever one is the drivers side). Subaru has a oil additive, kind of like seafoam that they recommend for the issue. Well, as soon as I put that in and ran it, the pressure switch started to leak. The tech's theory was that once it was cleaned, whatever crack that was gummed up to cause my code was now open and leaking. He had seen it on cars that switch from regular oil to synthetic later on in life and always around 100-130k miles (mine was 113k when it happened).

I replaced both of them because the parts were cheap and I was driving 2+hours one way for work at the time.

IMO I think they are just a wear item like PCV or something. The independent shop that I talked to about this recommends doing it at the timing belt service if the car has them.
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Old 11-07-2014, 11:58 AM   #4
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Quote:
Originally Posted by lpxltt View Post
I had something similar. It started with a p0028 or 26 code (what ever one is the drivers side). Subaru has a oil additive, kind of like seafoam that they recommend for the issue. Well, as soon as I put that in and ran it, the pressure switch started to leak. The tech's theory was that once it was cleaned, whatever crack that was gummed up to cause my code was now open and leaking. He had seen it on cars that switch from regular oil to synthetic later on in life and always around 100-130k miles (mine was 113k when it happened).

I replaced both of them because the parts were cheap and I was driving 2+hours one way for work at the time.

IMO I think they are just a wear item like PCV or something. The independent shop that I talked to about this recommends doing it at the timing belt service if the car has them.

Interesting, seems quite viable.

but to clarify, in my case my car is at 135,000 KM, and the timing belt service in km is 160k. but that is pretty close.
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Old 11-07-2014, 12:02 PM   #5
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And to follow up I did replace the sensor last night and it solved the problem, so confirmed that it was the VVL oil pressure sensor which leaked 1/2 a quart of oil in under 30km (18miles) of driving within one day.
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Old 11-07-2014, 12:47 PM   #6
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Part number is:

25240AA060
________________


BIG WARNING!



DO NOT THREAD IT IN ALL THE WAY!


take note of how the factory one on your car is only about half threaded in. it seals just fine and is still very tight. by tightening all the way down you will more than likely crack the threading into the block and make a much bigger issue.



DO NOT TIGHTEN THIS MUCH:

NOT MY CAR, but as an example, Picture from: https://www.toronto-subaru-club.com/...64&postcount=8


Last edited by Duvanator; 11-07-2014 at 01:59 PM.
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Old 11-07-2014, 01:05 PM   #7
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Hopefully some jb weld can hold that shut for a little while.
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Old 11-11-2014, 04:04 AM   #8
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i had the same thing happen on my 06 2.5i in around 250,000km the front drivers failed and started weeping, i changed it out big deal its like a $20 part. maybe a month later the rear passenger one started leaking so same thing another $20 part. I have heard the AVLS 2.5's had this issue but i have also heard the whole solenoid assembly fails? I almost wonder if some A-hole parts guys are selling the whole solenoid assembly instead of just the pressure switch?!?!?

I now have 280,000kms on it and everything is fine and the solenoids are leak free and working fine,
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Old 11-11-2014, 08:47 AM   #9
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Quote:
Originally Posted by Subie_Chris View Post
i had the same thing happen on my 06 2.5i in around 250,000km the front drivers failed and started weeping, i changed it out big deal its like a $20 part. maybe a month later the rear passenger one started leaking so same thing another $20 part. I have heard the AVLS 2.5's had this issue but i have also heard the whole solenoid assembly fails? I almost wonder if some A-hole parts guys are selling the whole solenoid assembly instead of just the pressure switch?!?!?

I now have 280,000kms on it and everything is fine and the solenoids are leak free and working fine,
This. Subaru wanted me to replace the solenoid at like $200 and another $200 for labor due to where the bolt is. I talked with an independent mechanic that specializes in Subaru and he told me the easiest way to test was to swap the two side from side if the Subaru branded cleaning solution didn't work.

Long story short, it is easy to take the passenger side one out but the drivers side you either have to a.) take the timing belt cover off to remove the bracket that is in the way of the bolt or b.) File the bracket a bit so the bolt has clearance (if you look you will see what I mean).

Luckily I didn't get to that point because even though the cleaning solution didn't fix the issue, it showed me exactly where it was.
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Old 11-11-2014, 09:48 PM   #10
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The factory torque specification for that switch is 12.5 Ft. Lb.
That will avoid damaging the valve housing. You should also apply sealant to the threads per the FSM.
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Old 11-13-2014, 01:14 PM   #11
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Quote:
Originally Posted by lpxltt View Post
This. Subaru wanted me to replace the solenoid at like $200 and another $200 for labor due to where the bolt is. I talked with an independent mechanic that specializes in Subaru and he told me the easiest way to test was to swap the two side from side if the Subaru branded cleaning solution didn't work.

Long story short, it is easy to take the passenger side one out but the drivers side you either have to a.) take the timing belt cover off to remove the bracket that is in the way of the bolt or b.) File the bracket a bit so the bolt has clearance (if you look you will see what I mean).

Luckily I didn't get to that point because even though the cleaning solution didn't fix the issue, it showed me exactly where it was.

This is incorrect, I was able to change my driver side switch with a 15/16ths deep socket and a short extension. no trickery or filing, or removing covers.

UNLESS you are referring to the entire solenoid assembly
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Old 11-13-2014, 01:16 PM   #12
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Quote:
Originally Posted by Elbert Bass View Post
The factory torque specification for that switch is 12.5 Ft. Lb.
That will avoid damaging the valve housing. You should also apply sealant to the threads per the FSM.
Exactly, I used a bit of teflon tape, no issues
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Old 11-13-2014, 02:04 PM   #13
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Quote:
Originally Posted by Duvanator View Post
This is incorrect, I was able to change my driver side switch with a 15/16ths deep socket and a short extension. no trickery or filing, or removing covers.

UNLESS you are referring to the entire solenoid assembly
I am referring to the solenoid itself as the code if for a faulty solenoid. You test by swapping them side to side and if the code follows the solenoid then it is faulty. If not then it is the pressure switch.

The bracket is in the way of the bolt that holds the assembly in. It will not physically back all the way out.
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Old 11-19-2014, 07:41 PM   #14
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Also had both of these start leaking on my 06 2.5i last year. Probably about 90k miles on it. It seems to be a standard failure mode around the 100k mile mark. I know I have a few subie friends that have also seen it.


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Old 11-24-2014, 10:52 PM   #15
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When you have a problem they are 100-140 us. Also if they are worn Change your oil like you love your subi. They fail in cars with high amounts of oil contaminants and after turbo failure you'll chase your tail. Good rule of thumb if you change a solenoid change your pressure switch. They cost like $40.

They are both easy to change. No goo either just some Teflon tape.


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Old 09-13-2015, 05:53 PM   #16
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Default It's Cracked Now what?

Quote:
Originally Posted by Duvanator View Post
Part number is:

25240AA060
________________


BIG WARNING!



DO NOT THREAD IT IN ALL THE WAY!


take note of how the factory one on your car is only about half threaded in. it seals just fine and is still very tight. by tightening all the way down you will more than likely crack the threading into the block and make a much bigger issue.



DO NOT TIGHTEN THIS MUCH:

NOT MY CAR, but as an example, Picture from: https://www.toronto-subaru-club.com/...64&postcount=8

So I cracked mine. Now what do I do? How do I fix/replace this?


Thanks
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Old 09-14-2015, 10:57 PM   #17
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Remember Alumaloy melts at just 728 degrees and it's stronger than the base metal. You can machine it, drill it, tap it. Fix your broken boat propeller and save $80. Fix this broken ladder and save $100.

Fix your cracked cylinder head and save $2000? Um, maybe if you put $2000 worth of work into it you can rescue that head. But I think it would be a break even deal on the money, a big loss on the time, and a big loss on being sure you didn't roach something else with the head heating it up to 728 degrees with your hardware store propane torch.
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Old 10-30-2016, 06:48 PM   #18
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Default Just a though

Kinda late but if you still haven't fixed this I would try silver solder.
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Old 10-24-2017, 03:17 PM   #19
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Default Oops I Cracked My Head Vvl Fix!

Quote:
Originally Posted by frost240z View Post
So I cracked mine. Now what do I do? How do I fix/replace this?


Thanks
I broke it as well and refused to pull the head... 07 outback 2.5. First remove ac lines from your way.. What I did was widened the thread hole with a drill bit/dremel down to the break (i busted the whole side off in a couple chunks when threading in a new oil pressure switch). You need to widen the area a bit to make room for the thickness of the following extension pipe walls.. So she don't go in **** eyed don'tcha know. I picked up a coupling, female to female, and small threaded on both ends, pipe. Hollow to act as an extension, only about 2" long or so from the hardware store found in the plumbing section. Same threads as oil switch. I got appropriate tap and drill bit for the pipe size/threads.. Drilled down in the oil channel to before the port that goes to the valves etc then worked the ol tap down maybe 3/8". Back and forth in and out its all in the hips. Shopped vac'd out all the metal bits. Made a straw nozzle for the vac hose to get down in (alum arrow cut or bic pen disassembled) Mixed up some epoxy and lightly applied it to the pipe threads and threaded 'er in. Wicked careful like. Wrapped the top of that ext pipe with teflon tape then threaded the coupling on.. Cranked it tight from the coupling but dont wait too long you know theres epoxy on them there threads guy. Tighten from the switch if you want son. Its 15/16 btw. Then the oil switch.. I also extended that one white wire but you might get lucky.. Tighten all this as to what you feel comfy with. You may want to wait on epoxy around base to see if you tightened enough - take for a drive - check for leaks. I then applied more epoxy around the base to reinforce and boom hang on , BOOM! Saved 2k. I had to say that louder because thats how you'll feel. Good luck! Message me if you have questions or need details. I hope this helps people.
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Old 07-01-2019, 08:49 PM   #20
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I have the same problem. Sadly, this happened two months after I had the engine out for head gaskets job.
I'm planning to try the JB weld solution, have anybody tried to glue the sensor in? I would buy a new one and use JB weld to keep it in place.
Any concerns about it?
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Old 07-06-2019, 08:44 PM   #21
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Quote:
Originally Posted by Duvanator View Post
BIG WARNING! DO NOT THREAD IT IN ALL THE WAY!
THIS. Since I didn't have a socket extension, I tried to squeeze in there... and managed to over tighten my new sensor despite using a torque wrench. Went from a slow leak to oil sprayed all over the entire engine compartment — couldn't see the crack from the front side, either.

On the plus side, the pressure light lit up!

End result: sold the car to a mechanic. With all of the work it needed, I pretty much totaled the car because I couldn’t be bothered to buy a damn socket extension. Moral: use the right tools.
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Old 07-14-2019, 02:30 AM   #22
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Default JB Weld results

Instead of gluing in the oil pressure switch, I decided to glue in an 1/8 NPT male to female fitting. Unfortunately, in PrincessAuto had only the one with the loose nut. I JB-welded it in not knowing that it won't properly fit the sensor. Luckily, I was able to buy a proper fitting and now I have two fittings before the sensor. So far the car drove a couple hundreds km and no issues.
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Old 07-19-2019, 02:59 PM   #23
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Default

Quote:
Originally Posted by Elbert Bass View Post
The factory torque specification for that switch is 12.5 Ft. Lb.
That will avoid damaging the valve housing. You should also apply sealant to the threads per the FSM.

I had to deal with this sensor too, recently.
2007 legacy, 185k miles.
Both sensors were leaking (driverís & pass.) and what I should have done was to torque them down a little more, and see if they continue to leak.
Instead, I decided to replace them (bad idea), and of course, the cylinder head cracked for both sides.
Solution: DE-GREASE multiple times the nest where the sensors bolt into, apply some ORIGINAL jbweld onto the NEW sensor (from the dealer), stick it in there, allow 2 days to cure fully, and keep on riding the car!
Worked for me! Yea, a lot of work, but better than a new car payment.
Good luck!
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Old 07-19-2019, 03:12 PM   #24
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Default

Quote:
Originally Posted by Elbert Bass View Post
The factory torque specification for that switch is 12.5 Ft. Lb.
That will avoid damaging the valve housing. You should also apply sealant to the threads per the FSM.

This is a dangerous sensor to replace!!!!!!
The cylinder head cracks real easily, in no time! Think 5 times before you do something to it! You can expect the worst!
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