Oil Wars (P164B)

[JonA]

9.20 update: I believe the fix is in. I think that the high oil pressure switch that most online parts catalogs show you (2.3-2.8 BAR) is wrong. I replaced mine with a 2.5-3.2 BAR switch as specified in the service manual, and after test driving 50-60mi, have not had the issue return. The part number is 06E919081C. ShopDAP has it, and parts.vw.com has it cheaper, but parts.vw.com says that it's for a different car.

Finally got the 09 Touareg V6 TDI back from the shop after having them attempt a fix for an "Oil Pressure - upper limit exceeded" warning (and additionally replacing all the e-brake hardware). In my searching, it appears to be a semi-common issue without terribly clear answers, so I thought I might document my experiences here. Along with the error on the dash and limp mode (which both go away upon restarting), the issue is accompanied by code P164B - Oil pressure switch Malfunction Upper limit exceeded.

I've done a bunch of reading and found this SSP on the CATA engine's oil management mechanics (pg 15-16, or if you're looking at the page numbers written on the page, 11-12), but I'm putting all these bits of information together so my basic understanding may be incorrect... let me know if so and I'll edit as needed so future generations hopefully have an easier time than I did figuring things out.

SO, here are the main elements of the system that I think may be part of the issue:

• there is an approx. 0.75-1.05 BAR oil pressure switch (038919081M, grey plastic, single wire, lives inside the oil filter housing on top of the engine, a bit underneath the EGR to gain access it seems, labeled 0.9 BAR in the service manual)
• also an approx. 2.3-2.8 BAR oil pressure switch (059919081G, green plastic, two wire, lives on the front of the engine, a bit right of center and below a pulley, 2.5 to 3.2 BAR specified in service manual... strangely the service manual also specifies "grey insulation," but I've only seen it in green so far.)
• and an oil pressure regulation valve (059115243B, metal, lives right next to the green oil pressure switch on the front of the engine) This one was the toughest to figure out. Currently, if you search for this part on FCP, it will come up as a "VW Camshaft Adjustment Solenoid" which is a mislabeling in their system confirmed by an employee... if you search for this part on ECS, it won't tell you what cars it fits.

Here's what seems to be happening, and this is where my understanding is probably even more questionable:

• when the oil is cold, and up to approx. 88c (not noted in the SSP but read in various comments and seems to hold true to experience), I believe the 2.3-2.8 BAR switch is used (oil pressure will be higher because it's lower temp and therefore thicker, right?) (this is when the oil pump is in its "flow rate-controlled" state)
• when the oil reaches 88c, and when RPM is over 2500, the oil pressure regulation valve will switch off, closing an oil duct, which adjusts the oil pump into its "high delivery rate" state, and I believe begins checking the state of the 0.75-1.05 BAR oil pressure switch
• so, my thesis is that the old, corroded oil control valve doesn't switch at just the right time (like this user suspects on the VCDS forum), thereby causing a momentary difference between expected and actual status of oil pressure switch status

Will report back after replacing the valve, since it's slightly easier to access than the 0.75-1.05 BAR switch, and only about $50. If that fails to fix the issue, I also ordered the 0.75-1.05 BAR oil pressure switch.

The 2.3-2.8 BAR switch has been replaced and the issue remains. Completely anecdotal, but I think it might have alleviated it somewhat. It used to seem like it would go into limp mode much more frequently, but now it only happens if oil temp is 88c or higher and RPM is above 2500. If the oil is cold, I can jam on the throttle a fair bit without tripping the code.

---

Some images that should help place the switches and valve.

Below is the low pressure switch, which according to the service manual, you'd need to remove the pump for EGR and coolant hose to access, and requires special tool "T40175" which appears to be a 24mm jointed deep socket.

Below is the procedure for removing the oil pressure valve, circled are the SW = green higher pressure switch, and VLV = oil control valve.

The post on the VCDS forum by andythechief was instrumental to my (hopefully correct) understanding of the issue, and he did a lot of good diagnostics that were very helpful. Also helpful in understanding the issue was this video on YouTube. I don't think it's a CATA (DGT? not sure if that's the engine code) so the grey oil pressure switch is in the green oil pressure switch's spot on his, but he shows an example of how the oil pressure switch fails (which is apparently not uncommon either). A less helpful, but interesting read over from Club Touareg is one of the top results on Google when searching the code.

 

[oilhammer]

Can't speak directly to the CATA engine, but other VAG engines, most notably the EA211 (1.4/15L) and EA888 (1.8/2.0L) have a fairly common problem of oil pressure control solenoids and oil pressure sensors.

I put a BRAND NEW engine in a 2015 GTI (CXCB engine, a 2.0L member of the EA888 family) that came with both the oil pressure regulating valve and piston cooling jet control valve already installed. I purchased all three of the sensors new to go with it, specifically because I didn't want any troubles.

Turns out, the BRAND NEW piston cooling jet control valve was bad right out of the box, then once I got it replaced, the brand new oil pressure sensor was also bad.

I'm sure your engine uses components that are similar/same. I replace the oil pressure control valve in the 1.4L all the time.

So you are likely on the right track here. QC has gone to crap lately.

 

[PRY4SNO]

Turns out, the BRAND NEW piston cooling jet control valve was bad right out of the box, then once I got it replaced, the brand new oil pressure sensor was also bad.

Wait, what?

So... couple questions.

Can one proactively check for something simple like a PN suffix (rev) to ensure acquiring a quality part? Brand/manufacturer? Can one use a multimeter at the counter prior to install to verify condition (since electronics rarely have warranty)?

Are these kinds of failures limited to oil pressure sensors/valves, or are you seeing this across the board?

 

[oilhammer]

We've been seeing a drop in QC of replacement parts across the board. Bad out of the box happens all too often.

Usually it gets traced back to the least common denominator: China.

 

[JonA]

A tragedy in two parts:

For those who don't know how it should have come out of the engine:

I can fit a pair of needle nose pliers in there, and I can kind of get some channel locks in, so I tried fiddling with the sleeve that is stuck in there and I didn't see ANY play at all. Absolutely none. It's completely frozen in there as best as I can tell. I think it became one with the engine.

Sooo... if anyone has any incredible extractor ideas, tools, tips, tricks, etc... feel free to drop them here. I'm going to drink heavily for a little bit, and then start reading up on how to remove the whole front end of this hunk so I can maybe tap the sleeve, put a bolt in there, and pull it straight out.

 

[braddies]

Possibly needle nose locking pliers like these?

 

[oilhammer]

Good gravy, the RUST!!! Man that looks terrible. Damn....

You may have to clear the path and get in there with a chisel or something and try to cave the broken part in on itself.

 

[325_Guy]

You may have to clear the path and get in there with a chisel or something and try to cave the broken part in on itself.

A dremel may work here also. I have the cable-driven remote head and a right angle attachment to give me additional dexterity.

If you can notch the cylinder from the inside and break it, you can twist it in on itself and break the bond between it and the bore it's stuck in.

Tedious, but doable.

 

[JonA]

Appreciate these suggestions a lot y'all. I'm going to give it a soak with some PB Blaster or the like, not look at it for the weekend, and start working on it next week.

I'll probably give it some gentle-ish knocks with a chisel first after letting it soak and see if I can knock any play into it, then pull with some needle nose vice grips (thanks @braddies, I don't have a pair so I always forget they exist). I'm now deathly afraid of breaking off the little bit sticking out so I'll be going easy with it.

I've also got that dremel adapter @325_Guy, another good suggestion. My only worry with that is damaging the bore but I like that idea... I'll keep that in my back pocket for if the less "dangerous" options don't pan out.

 

[oilhammer]

What part does that solenoid go into? Is it the block itself, or the front housing?

 

[JonA]

The block itself as far as I can tell

 

[oilhammer]

See I don't think it is... the block is cast iron, painted black. The front cover is aluminum. If the absolute worst came to it, you could take that cover off.

 

[oilhammer]

That's a CNRB, but I think it is similar... see on the lower left hand (right in image) of the engine in that pic? I think that is the oil pressure control valve there, and that goes into the upper oil pan or the front cover, really cannot tell and I don't remember. But your pic does look like it is going into aluminum now that I look at it closer... so that's not the block itself.

Bad news is, it is an enormous job to R&R the upper oil pan.

 

[TurboABA]

Looks like the flange simply rotted off the cylinder.
The only thing holding it in the bore should be the o-ring.
I'm assuming that all the oil has already puked out of the block at this stage, so I'd try to remove the remaining cylinder (more like a sleeve) using something like reverse pliers

 

[JonA]

My sense of engine anatomy is poor and your example looks very close to what I'm working with. It is definitely the aluminum cover on the front of the engine, so I guess worst case scenario in this case is not quite as bad as I originally thought. I'll look into the aluminum cover removal as a "just in case," but keep my fingers crossed that it doesn't come to that. Thanks so much for your insight.

 

[oilhammer]

OK, looks like it is in the upper oil pan:

Oil Pan Upper Part for 2016 Porsche VW Cayenne Touareg 3.0 TDI CVV CVVA MCV.VA 2 | eBay

Best pic I could find...

So good news, bad news. Good news is, it is a part that comes off of the engine. Bad news is, it isn't going to come off without a lot of work. And by " a lot of work ", I mean Step 1 is remove the engine.

So yeah, let's hope you can get the broken stump out of there. Because as summarized in the thread I posted on the CNRB, you basically are taking the engine out and tearing it down to just the block/heads in order to R&R the oil pan:

2014 CNRB reseal | TDIClub Forums

And as I did in that case (and another later), I just resealed and replaced anything and everything along the way to make sure it didn't have to come back apart again for as long as possible.

 

[TurboABA]

What part does that solenoid go into? Is it the block itself, or the front housing?

Visual from manual

 

[oilhammer]

Yeah, I have all that... I was looking specifically for an actual picture, which I posted. Thanks for confirming though.

 

[TurboABA]

Etka gives a good view of it too... and here's another pic for extra clarity.

https://http2.mlstatic.com/D_NQ_NP_2X_716670-MLM69392570943_052023-F.webp

 

[JonA]

Attempted to get it to shimmy out by using a pry bar while tapping at it and applying penetrant over the last couple days, but no joy. Needle nose lockers also failed. Flange has mostly broken off, so at least I know that's probably not what's keeping it in now. Next up, reverse pliers. Failing that, my tap is ready to go.

I couldn't even get it to turn in the slightest with the pry bar / hammer, so I'm not terribly hopeful for the pliers, but trying to leave tapping as a last resort since it seems with my luck, it'll break in there, or I won't thread it straight, or something else horrible. Guess there's always the Dremel, too, but it always makes me a little uneasy, especially something stuck inside like this. More potential ways to mess up in a way I can't recover it (for me at least).

Definitely going to grease up the flange / shoulder area if I ever get the new one in. Thanks everyone for the diagrams / photos / tips. It's given me enough confidence to keep at it a while longer before throwing in the towel. Here's hoping round three will be a winner... This car is currently winning the title of Nicest Car I'll Never Drive.

 

[JonA]

Oh my god. It's out. Went in with the tap around 6, just finished extracting about a half hour ago. Anyone have the book time on this thing?

The winning extraction concept pictured below, the brain child of my dad, MB master tech of 45+ years of experience. Dad, if you're reading this, I love you. Remember kids, father knows best. If anyone ends up in a similar bind, here are the parts I used to pull it, readily available at the O'Reilly down the street, with generic info as well as brand specific p/ns:

• Bolt: M8-1.25-60 / Dorman 980-455
• Nut: M8-1.25 / Dorman 982-008D
• Washers: 1/2in ID, 7/8in OD / Dorman 965-014D
• White lithium grease

I saved this method for last because I was afraid to break the tap inside the sleeve and make this completely irrecoverable for me, but as dad advised, I took a lot of time and care with it. Tapped slowly, getting only 2-3 full turns before backing all the way out, reapplying lithium grease to the tap, and cleaning the particles off. Took a long time thanks to the tight working area. I thought after getting the sleeve past the O-ring it'd slide right out, but no joy. Wasn't even able to pry it out once either of the incut rings were visible. Had to use a couple different depths of socket with my makeshift puller to get it all the way out.

The puller in situ:

Pictures of the offender:

And the NOW EMPTY BORE

Tomorrow, I'll run down to O'Reilly (hopefully the last time for this project) for some fine grit wet/dry sandpaper that I'll oil up and use to clean up the face and shoulder of the bore. I really made a mess of it with all the chiseling, but it did end up making the sleeve fit better in the deep socket I pulled it into. Big thanks again for everyone's advice and knowledge (325_Guy, braddies, oilhammer, and TurboABA, makes a big difference to have helpful and knowledgeable people on your side). And of course HUGE thanks to dad.

If this doesn't fix the oil pressure issue, I'll R&R the low oil pressure sensor in the oil filter housing, but after this, I feel like it can't possibly phase me.

 

[oilhammer]

Awesome!

I'd be sure to clean out that hole thoroughly, as any debris will be DIRECTLY in the oil supply. And maybe after it's all together, run it for a few minutes then CHANGE the oil and filter.

 

[325_Guy]

Yes, outstanding!

And thank you for posting your success. Somebody someday will be stuck in the exact same place and hopefully they search and happen on your post.

 

[JonA]

Thanks for your kind words. Here's hoping future travelers have PCVs that slide right out clean... When I put the new one in (after vigorous cleaning of the face with sandpaper, and the bore with oily paper towels), it slid in so easy, I felt a little cheated.

Alas, another P164B on my test drive... Next up, the last oil pressure sensor in the loop. If that doesn't do it, I'll probably bring it back to a real tech so they can tell me if it needs an oil pump or what. I don't feel bad about spending all that time on the PCV since it looked so terrible... probably would've needed to be done eventually. At the end of the day, I'd rather do something like that myself and hate it than spend lord knows how much to have someone else do it.

Anyway, looks like this low pressure switch requires access via removing the EGR pump? Supposedly also requires a special 24mm extension-deep-wobble socket to remove the switch. Will throw a pic of the service manual up later on. Maybe I'll get into it tomorrow and see if I can make do with what I have.

 

[JonA]

Hrm... service manual claims I need to drain coolant, but it isn't at a terribly low point on the engine. The coolant drain process as laid out in the service manual is six pages and uses a total of seven special VAG tools? Seems a bit excessive to me. Let's see if I can get away with just spilling a bit and refilling. Gotta find something to cap the hoses off with though, I don't have any of those hose pinch pliers and my toolbox is already quite stuffed (plus all money is currently devoted to making the Golf pretty).

 

[JonA]

Everything went nice and easy, until finally removing the switch. Didn't need to do all the service manual calls for (who's surprised), I was able to just pop off hoses (2) and (3) in the service manual, shove the EGR cooler pump out of the way, stuffed a 1/4" to 3/4" socket adapter in the hose and managed not to spill much coolant. Then stuck a long screwdriver / prybar down from the top while unlocking the clip to slide it out. Everything came out nice and easy.

I tried shoving a 15/16" socket in there (O'Reilly did not have a 24mm), but it's too bulky. For a sec I got worried I'd got it stuck in there semi-permanently, but remembered I could pry it out from the top while giving it a twist with the ratchet. Panic's a helluva drug.

Ordered the T40157 from vw.snapon.com after struggling to create an account for 10 or 15mins. Now the waiting... I should probably reconnect the coolant lines in the meantime to prevent any junk or condensation from getting in there. What I soaked up with a white paper towel looked fairly clean, putting a coolant flush on the "not doing" list.

 

[JonA]

Welp, the parts cannon has failed. Stuck the low pressure sensor in, test drove, and eventually the code returned. If anyone wants to borrow T40157, I'm happy to lend. It's a must have tool for this dumb spot it's stuck in. Maybe it's time to test wiring? Guess I'll have to find a schematic. Last parts possibility is oil pump, right? But trying to avoid throwing more parts at it... unless that's the last one.

Some more research:

• this poster claims pulling and cleaning the oil pan resolved the issue, another poster in that thread claims oil pump solved it (but then renegs, it didn't).
• This one says N428 fixed it (if only).
• This one says oil pump, sump, strainer, and pressure valve (doesn't specify which) solved it.
• This one replaced oil filter, filter housing, N428, N522, PCV and pump (on a TFSI), and still didn't solve it.
• This one thinks it's balance shafts.

Could it be that one of the oil pressure switches is incorrect and therefore giving incorrect info? While replacing the latest switch, the one I pulled was the same pressure range (0.75-1.05BAR) as the one I put in, but I didn't replace the high pressure switch myself, so I'm not sure if it was the same. Another possibility is the PO put the wrong switch in the high pressure spot at some point.

Maybe the high pressure switch needs to be able to accommodate higher pressure (guessing as I'm seeing upper limit exceeded in the code). The one that I bought to replace the high pressure sensor is 2.3-2.8 BAR, but 2.5-3.2 is specified in the service manual (seen after buying). Maybe I've gone on a wild goose chase because the sensor is the wrong pressure. The 0.75-1.05 is specified to be 0.9 BAR in the service manual which seems close enough (and within the range), so my current best guess is the high pressure one might be wrong.

I've also seen that there are some O-rings in the oil filter housing on an oil drain valve that can wear out on some engines, but I'm not sure the CATA has that. Guess it's time to poke around some more.

 

[PRY4SNO]

Nothing to add, other than kudos to you for your persistence. I admire your willingness to stick it out and post the results for the rest of us.

 

[TurboABA]

Riddle me this... have you actually put a mechanical gauge on the thing to confirm that there is low pressure or whatever... or are you just replacing everything while possibly dealing with a flaky sensor\connection?

 

[JonA]

Nothing to add, other than kudos to you for your persistence. I admire your willingness to stick it out and post the results for the rest of us.

As they say, if you're gonna be dumb, you gotta be tough.

Riddle me this... have you actually put a mechanical gauge on the thing to confirm that there is low pressure or whatever... or are you just replacing everything while possibly dealing with a flaky sensor\connection?

It's a whole new can of worms to me, but I definitely should do that... originally didn't because I don't have one, and was so sure of my original diagnosis (heh) that it was cheaper to just buy the parts.

Since it's rev limited to 2500rpm in park/neutral and needs to be running over 2500rpm with the oil hot to trigger the code I'd have to be driving. I haven't used an oil pressure tester before, is it easy enough to put it on and drive around with it on the dash or something like that?