Fun With Cam Chain Adjusters. What's your speculation??

[old guy]

Here's the deal......

Back in May of this year my engine developed a nasty noise. Long story short, it ended up being a defective water pump bearing. During the process of finding the issue I replaced the cam chain adjuster. I figured at 190k+ miles it was a reasonable PM to perform. So the timing chain adjuster was replaced along with a complete TB service (TB, water pump, TB tensioner, idler pulley etc). The OEM timing chain adjuster was still functioning OK but upon removal the wear pads had some significant wear. Life was good for three months.

Then in August I started getting a P0011 and a P0012 indicating an over-advanced or over-retarded intake cam. Since I never had these codes in the previous 190k+ miles I had to assume a defective cam chain adjuster. I contacted the supplier and had the adjuster replaced under warranty. Life was good for another three months.

Then last Friday I put ~600 miles on the car. I stopped at the Hospital on the way home to visit a coworker and when I went out and started the car I was graced with a CEL for a P0011. I reset it and on the trip from the Hospital to home (10 miles) I was the graced with a P0012. (over advanced / over-retarded cam position codes). Since then I no longer get a P0011/0012 but I do get a daily P0340 and I have a bad idle with reduced vacuum. My speculation is that the cam adjuster is now stuck in the middle between full retard and full advance. Consequently the ECM doesn't know what the hell is going on since the cam position sensor can't tell if the cam is at full advance or full retard. So it gives me a P0340 position sensor malfunction code since it doesn't know what else to do.

I should mention that I had a spare cam position sensor and changing it made no difference. The cam position sensor is getting a 5v trigger signal as it should and the cam adjuster solenoid is getting a 12v activation signal as per spec. I checked the resistance on the OEM solenoid activator as well as the replacement solenoid activator and both were at 13Ω resistance. According the the Bentley it should be between 5-8Ω at 20°C. Technically it is out of range but when I apply a 12v signal I can hear both of them activate so I don't think that is an issue.

So what are the chances that I received two defective cam adjusters? Although it seems highly unlikely I am running out of things to check. So here is what I am going to do this weekend. I ordered and received replacement wear pads for the OEM cam adjuster. Tomorrow or Sunday (weather permitting) I am going to replace the replacement cam adjuster with the OEM one and see if the problem goes away.

So wadda you think?? Will it fix the problem? Do I have some other issue that I need to address? I'm getting pretty tired of replacing the same part over and over again. All suggestions are appreciated. Bad adjuster? Lightning strikes twice in the same place or something else going on?

[Matt Devo]

I'd swap just the solenoid from your OEM/original CCT into the current one, since it's only two screws, even though they both have the same resistance. The chances of the CCT itself being bad strike me as pretty low. Another (somewhat unlikely) possibility is the CCT isn't getting enough oil pressure.

[old guy]

I'd swap just the solenoid from your OEM/original CCT into the current one, since it's only two screws, even though they both have the same resistance. The chances of the CCT itself being bad strike me as pretty low. Another (somewhat unlikely) possibility is the CCT isn't getting enough oil pressure.

When the first cam adjuster started giving me a P0011/0012 I tried replacing the solenoid with the OEM one and it made no difference. I also checked the oil pressure to make sure that wasn't an issue. Oil pressure was fine at the time so I don't think it is an issue three months later. I was planning on checking it again though just for peace of mind. And I agree that the likelihood of two bad adjusters doesn't seem reasonable.

Thanks for the input!

[Matt Devo]

in that case, I'd check the tension in the timing belt, and then pull off the VC and inspect the CCT / chain timing

[JHarris]

I am battling an issue of the same sort. P0011 sometimes right away after clearing, sometime take a day. I have replaced the chain tensioner with a MTC from ECS, I have also replaced the cam gasket, cam chain, cam position sensor (twice) oil pick up screen. I am at a loss. I hope you get yours figured out.

Jesse

[old guy]

in that case, I'd check the tension in the timing belt, and then pull off the VC and inspect the CCT / chain timing

We think alike. I checked the timing belt tension the first time this problem occurred and even tweaked it a little tighter. I also replaced the chain along with with the warrantied adjuster.

[old guy]

I am battling an issue of the same sort. P0011 sometimes right away after clearing, sometime take a day. I have replaced the chain tensioner with a MTC from ECS, I have also replaced the cam gasket, cam chain, cam position sensor (twice) oil pick up screen. I am at a loss. I hope you get yours figured out.

Jesse

I will certainly post a follow up after I stick the OEM one back in.

[JHarris]

If I can find my OEM one I will try that also, I thought I kept it.

[old guy]

If I can find my OEM one I will try that also, I thought I kept it.

Before you replace it you might want to consider replacing the wear pads if yours are showing a lot of wear: Clicky click . Cheap enough! I ordered them last Saturday and received them yesterday.

[JHarris]

I think mine looked ok. I am pretty sure some time in this cars life it has had a remaned head put on it. There is no stamping for the motor code on the head, ,just a cleaned machined surface.

[customa4]

OG, what do you as far as the valve cover gasket when you do this work. I can't imagine you replace it every time? Do you just use some new RTV gasket sealer and get it back together?

[old guy]

OG, what do you as far as the valve cover gasket when you do this work. I can't imagine you replace it every time? Do you just use some new RTV gasket sealer and get it back together?

I replaced the valve cover gasket at 100k miles since it was leaking. I replaced it again with the first cam chain adjuster replacement (190k+ miles). I reused it when I replaced the adjuster after only three months. It sealed fine. I did replace the cam adjuster gasket again. I used the valve cover gasket "as is" both times and only added a small dab of RTV at the corners. I do have a new valve cover gasket and cam adjuster gasket for this weekend and will probably replace both sine I have them and they are relatively cheap gaskets.

[customa4]

Alright, good to know. Thanks. Good luck fixing this problem.

[Spike00513]

When the first cam adjuster started giving me a P0011/0012

Can you please post the entire code? Here is an example:

17522 - Oxygen (Lambda) Sensor; B1 S2
...........P1114 - 004 - Internal Resistance too High - MIL ON

[old guy]

16395/P0011/000017 - Bank 1: Camshaft A (Intake): Retard Setpoint not Reached (Over-Advanced)

16396/P0012/000018 - Bank 1: Camshaft A (Intake): Advance Setpoint not Reached (Over-Retarded)

[Spike00513]

16395/P0011/000017 - Bank 1: Camshaft A (Intake): Retard Setpoint not Reached (Over-Advanced)

16396/P0012/000018 - Bank 1: Camshaft A (Intake): Advance Setpoint not Reached (Over-Retarded)

What about the constant P0340 one?:

Consequently the ECM doesn't know what the hell is going on since the cam position sensor can't tell if the cam is at full advance or full retard. So it gives me a P0340 position sensor malfunction code since it doesn't know what else to do.

[old guy]

16724/P0340 - Camshaft Position Sensor (G40): Malfunction

[Spike00513]

Ross-Tech:
Possible Causes

Wiring from/to Camshaft Position Sensor (G40) faulty
Camshaft Position Sensor (G40) faulty
Timing misaligned

Possible Solutions

Check Wiring from/to Camshaft Position Sensor (G40)
Check Camshaft Position Sensor (G40)
Check Timing

------------------------------------
I can't comment on checking timing or the sensor since I know nothing about this (yet), but I think it'd be worth it to inspect the wiring and connector. Maybe a rodent chewed a wire? Or the connector broke? We all know what happens to VAG plastics after 10 years of sitting in a hot-engine bay. If the connector locking tab (or any other parts of it broke), you can get improper CPS operation. I replaced my connector for $3, which took care of my following code. Note, my code will differ to some extent due to my engine being a 3.0, which has 4 CPS's. The issue was with the connector at position G301, which is at the top pass. side of the motor. I had bad idle, and I think poor vacuum, in addition to the CEL caused by this code. It would only come on after the 2nd time of driving the car, after ~10 minutes. Upon inspection, I saw that the locking tab was broken. That is basically like having a lamp barely plugged into a wall-socket during an earth-quake. It will probably flicker. Whereas an intact locking tab, keeps the "lamp socket prongs" (aka CPS connector) plugged in all the way and making constant, good electrical contact.

19759 - Exhaust Camshaft Position Sensor Bank 2 (G301)
..............P3303 - 001 - Open or Short to Plus - MIL ON

-I'm still thinking and trying to figure this out, but for now, it's a harmless start to pop the hood and give it a quick look (I assume its easily accessible, it is on 3.0's). Not only that, but it appears to be one of thing that you haven't yet checked.


--------------------
I assume there are ways to test the sensor itself in VCDS, but before getting into anything advanced, I'd do a quick look-see at the wiring and connector. Maybe try the following?

-rough up connector terminals, can be done by de-pinning them/removing them from the electrical connector housing and abrading with sand-paper
-spray w/ Electrical Contact Cleaner
-inspect pin locking tabs, make sure they're in the right position and not bent inward or outward (which would prevent terminal pin seating and contact)
-re-pin them into the electrical connector plastic housing
-apply dielectric grease
-carefully re-connect the connector while making sure not to bend any male pins (or force anything), which is easy to do if you're aggressive with it

Note:
-handling an old connector is likely to damage something, because its so old, dry, and brittle. Being gentle/careful is important. The purple locking c-clip breaks easily.
-if no de-pin tools are available, they can be made out of regular-size paper clips by bending them into shape, and grinding/sanding down the tips to the correct thickness if required

[old guy]

I have checked the connector and also checked for the required 5v control signal voltage. The control voltage is present at the plug so I know the wiring is intact. I also unplugged the sensor with the engine running and immediately got a code for an open circuit so I know the connector is good. My assumption is that the code is being generated for a cam timing issue. Normally the intake cam is either in the full retard (0°) position or the full advance (22°) position. If the cam chain adjuster is stuck between the two the sensor cannot get a reading at either end of the range so the ECM has to assume a timing issue and gives a P0340. At least that's my theory.

Another indication is that I now have a lumpy idle and a loss of vacuum at idle. Normally my idle reading is 21-22 inHg. It's now at 18 inHg. This occurred at the same time the P0340 started popping up. This is what I would expect to happen if the intake cam was running with excessive advance. Kinda like the lumpity lumpity lumpity idle of the old school high performance cams. As soon as I raise the idle a few hundred RPM's the vacuum goes to -21 inHg.

Sure hope I'm right and putting the OEM cam adjuster back in fixes everything.......

[ryanj]

I have replaced a ton of these chain adjusters at my shop and can tell you I have been worked over more times than I can count by aftermarket chain adjusters. I have installed probably 5 that I can think of that had 1 problem or another right off the bat and had to be replaced and several more that had problems a few months down the road. For awhile I would only install factory adjusters because I had no confidence in any aftermarket units, but about a year ago I started using Hudson brand adjusters (K revision) (from north side imports) and haven't had any problems with them since. What is your timing showing in measure block 91 when this is happening? A quick test you can do is hit the adjuster solenoid with a power probe while watching MVB 91 timing should advance to 22° relatively fast and then back down to 0° when power is let off. IF your chain adjuster is getting stuck this is a great way to catch it happening. Also some times when faults are stored for timing MVB 91 will not show an accurate reading until you clear the codes. If your old adjuster was working fine I would defiantly throw that back in and give it a try.

As for having a problem with you cam sensor I highly doubt anything is wrong with it. They tend to be super reliable unless you physically damage the sensor.

[old guy]

Thanks for the info! I'm now a bit more confident that the problem is with the aftermarket adjuster. I will give block 91 a quick check before I pull everything apart. I assume you mean to apply 12v to the solenoid with the car at idle? I should have thought about just checking it as is and see what it shows. I will do so in the morning after it warms up a little.

And I have cleared all the codes numerous times but the P0340 keeps coming back.

[ryanj]

Yes apply 12V at idle. I believe the top pin is 12+ and bottom pin is ground, but just check the connector to be sure as it has constant 12+ on one pin and ECM controls ground. What is Vagcom's exact definition of P0340? (I checked it on Ross-Tech wiki and doesn't look like a common fault I deal with when dealing with chain adjuster problems, but sometimes the definition on the wiki is different from the one given on vagcom and I'm used to seeing the definition on vagcom.

[old guy]

The definition is "Camshaft Pos. Sensor (A) Circ Incorrect allocation". This leads me to believe the sensor is working properly but it can't locate the 0° or the 22° position since the cam adjuster is stuck somewhere between the two.

[ryanj]

Hmm I cant say incorrect allocation is one I normally see, but I still would bet you don't have any actual cam sensor / wiring issues. I'm still betting chain adjuster is causing this. Just out of curiosity what brand was the adjuster labeled as?

[old guy]

Hmm I cant say incorrect allocation is one I normally see, but I still would bet you don't have any actual cam sensor / wiring issues. I'm still betting chain adjuster is causing this. Just out of curiosity what brand was the adjuster labeled as?

It wasn't branded but was advertised as being made by an OEM supplier.

[ryanj]

Gotcha. Here is a link to the hudson brand I have been using I believe MTC is exactly the same and probably others.https://www.fcpeuro.com/products/aud...oem-058109088k While I'm not saying its as good as the factory one I haven't been given a reason to hate them (yet) Like every other adjuster I have tried.

[old guy]

Thanks for the link. It is the same price I paid for mine. Sure hope the OEM one does the trick.

[texasboy21]

It wasn't branded but was advertised as being made by an OEM supplier.

EuropaParts?

[old guy]

Until I confirm the issue I'd rather not say. The supplier has been extremely accommodating. The first adjuster was replaced under warranty with no questions asked. The supplier was surprised to hear of an issue since they have sold 100 or more with no complaints. When I called back in three months they were pretty skeptical that one person would just happen to have received two defective parts in such a short time while at the same time receiving no other complaints. I have to admit that I would feel the same way.

After a lengthy conversation I convinced them that I wasn't some ham-fisted yahoo and that I was reasonably competent with my installation and evaluation of the part. We discussed my course of action to replace the tensioner with the original OEM one and go from there. They have stated a desire to do whatever it takes to satisfy the customer. I am hopeful that I will resolve the issue this afternoon or tomorrow. It's currently 17°f and a bit too cold to start wrenching on my engine.

[walky_talky20]

Fletcher, have you checked block 093 (cam phase angle)? This should show what the offset between crank and cam sensor. Good place to determine t-belt stretch/proper t-belt alignment. But also should reflect a cam adjuster that is "stuck".

At warm idle (VVT off), I would expect the cam phase angle to be within +/-3 degrees or so. I'm not sure how it behaves during VVT on state.

Now, the only thing that makes me think otherwise is your P0340 code. I'm with you that stuck halfway might confuse it enough to throw that. I'm thinking the only other explanation is one or more keyways that are starting to shear off. Usually this is the cam sprocket keyway. On a well-maintained car, I wouldn't expect this. But when there are funky timing codes, it's always best to check all aspects of mechanical timing.

Having dealt with these aftermarket adjusters on my car a bit, and having changed several failed ones with all sorts of different problems, I would not be surprised at all if you got 2 faulty units in a row. The only surprising part would be that they both had the same problem.

I bought 1 aftermarket unit that would constantly blow the fuse. Warranty replacement fixed that. The new unit would intermittently throw codes for over-advanced/retarded. The same codes you describe. I tested the VVT function using block 091. I did not manually energize. Just took it for a drive with data log. The VVT engages at low rpm/high load situations. Everything worked fine, so I ignored the codes. I assumed it was just taking a little bit too long to advance/retard under certain conditions (perhaps when cold). I decided not to worry about it. After a while, it stopped throwing the code. I decided that it "wore in" and all was right once again.

My Speculation:
- Another bad VVT (yo), or
- Other mechanical timing trouble (keyway issues)

[diagnosticator]

Have you tried disconnecting the battery, and/or running ECU adaptation channel value reset 00 or 000? Battery disconnect won't reset all the adaptation values to default, the defaults must be set running reset.

[old guy]

OK finally got this sorted out. Apparently lightning does strike twice. I went out after lunch, hooked up my VCDS and went to measuring block 91. The normal position for the intake cam is either 0° or 22°. Because of measurement variations the ECM recognizes an active camshaft adjustment angle from -3° to +25°. When the cam adjuster is off it should be between -3° to +6°. With the adjuster activated it should be between 16° and 25°.

When you cold start the engine the cam adjuster is activated so you should see the activated range of somewhere between 16° and 25°. I had a reading that was bouncing around 12° to 14°. I let the car idle until the adjuster deactivated and the cam angle only dropped to 10°. This pretty much confirmed my suspicion that the cam adjuster was sticking.

I pulled the adjuster out and give it a thorough examination. I noticed two things. The spring rate in the replacement cam adjuster felt at least twice as strong as the OEM spring rate. Also when I compressed the OEM tensioner the movement was smooth and fluid. I repeated the procedure with the replacement tensioner and it felt gritty. Next I pulled out the secondary piston from both the OEM and replacement adjuster and compared the shafts. As you can see there was considerable scarring on the replacement cam positioner shaft and apparently that was causing the positioner to hang up.



I am now CEL free, my smooth idle is back and the engine is running much smoother.

Time to go hit the Bulleit Bottle!

Cheers!

[DiertyEuroSpec]

Soo did you purchase a new OEM unit for the $700 price tag or put in your original OEM tensioner? From the pics its looks like you went back to your original one. Also when replacing CCT's would just changing out the pads suffice as this seems to be the only part the has wear on it. If the solenoid is working properly would you recommend just getting the replacement pads?

[old guy]

Soo did you purchase a new OEM unit for the $700 price tag or put in your original OEM tensioner? From the pics its looks like you went back to your original one. Also when replacing CCT's would just changing out the pads suffice as this seems to be the only part the has wear on it. If the solenoid is working properly would you recommend just getting the replacement pads?

I reused my OEM cam adjuster. I just replaced the wear pads. Lesson learned. Yes I would recommend just replacing the wear pads and putting the OEM one back in. I was doing what I though made sense and replacing the cam adjuster as a PM for a high mileage engine. Apparently it wasn't such a smart idea after all.

[DiertyEuroSpec]

Were did you get the pads from?

[old guy]

Were did you get the pads from?

There is a link in post #9.

[walky_talky20]

If the adjuster fails in the "TDI clanking sound" mode, I don't think replacing the pads will fix it. It is some sort of internal wear, I believe.

If you have a unit (OEM or aftermarket) with worn pads that is not clanky, and is not throwing codes, I would absolutely advise sticking with it and just refreshing the pads. It seems these aftermarket units can go wrong a lot of different ways. And even with warranty replacements, it is pretty annoying changing the same part several times.

[diagnosticator]

Yep.

[DiertyEuroSpec]

Yea I've got no codes and running pretty quiet for the time being but the pads didn't look too great last time I was in there. Will get a set of pads for the future.

[BlazinB5]

What do you guys think of this? $180 for a supposedly OEM unit.
http://www.europaparts.com/cam-chain...58109088k.html