Cam adjuster issues 2010 R36

[Gonads00]

Hey Guys/Gals,

I've got a few questions that I can't find answers to so I'm throwing up a new thread. Before I get too far into it, I'm just going to see if this one appears as I went to a bit of trouble writing a thread just like this one earlier and for some reason it needed moderators approval and has not appeared.

EDIT-all's good this time so here goes:

I bought a 2010 R36 (110,000km) cheap as it had a check engine light for camshaft/crankshaft sensor synchronisation issue. Clearing the code only worked for about 30 seconds. It started well, drove great but had about 2 seconds of valvetrain noise on startup and a slightly choppy idle.

A bit of reading suggested it may be a timing chain/tensioner/guide issue. Warm engine compression test gave readings of 210, 200, 210, 200, 190, 190 (psi) so the engine itself seemed pretty healthy and drove that way too. I started disassembly and once I got the cam cover off I noticed that the locking slot on the intake cam was not sitting horizontal as it should when all the timing marks on the cam sprockets were in the correct disassembly/reassembly position. I retrospect, this clearly indicates that the cam adjuster had was not 100% but hey-I'm experienced in Subarus and Fords so I thought it best to leave this one to the experts.

I booked the car in to have the timing chains/tensioners/guides replaced at a nearby VW workshop. I reassembled the car and it drove beautifully into town to drop off at the workshop. I left it with them and headed back a week later to pick the car up. I was told the car refused to turn over initially and that the technician who had done the work had then "re-timed" it and tried again. This time it would not start and compression testing showed results of 40-50 psi on all cylinders. The workshop contends that the issue is caused by the sudden complete failure of the cam adjuster on the intake cam. I've seen this with my own eyes-the intake cam can be moved from retard stop to advance stop (about 20 degrees I guess) without putting any force through the sprocket onto the timing chain. I expressed my disbelief that a an issue that had not progressed in the last 9 months of ownership would suddenly cause a catastrophic failure while the car is in the workshop.

Questions:
1. How common is a sudden complete failure of a cam adjuster that causes an engine to become inoperable?
2. Would a failed cam adjuster allow the cam enough range of movement between the advance and retard stops to cause contact between the valves and pistons?
3. Would a mis-timed cam timing causing piston to valve contact be enough to further damage the intake cam adjuster?

Sorry for the long-winded thread and if you've read this far, I certainly appreciate it. I love the car, I love mucking about with cars and I hope to get the car back and contribute to this part of the forum.

Thanks,
Ben

[h100vw]

1 Yes they just stop working.
2 Possibly
3 No, I dont think it would.

Disclaimer, I am no expert on the R36. A rare car, in the scheme of things, not much on them on the internet.

[Gonads]

Cheers for the reply. I think I'm going to have to suck it and see and learn the hands-on way. There may be a snail thrown on if the head comes off.

gotta look at it in a "glass half full" sense, right?

...Ben

[Gonads]

Nobody else with any experience on the R36 engine with cam adjuster issues? I'm looking down the barrel of picking up a stuffed car that drive beautifully when delivered and paying severel thousand for the privilege. Any advice would be appreciated.

Thanks,
Ben

[Passat my07]

I haven't worked on a r36 engine but normally the valves wouldn't hit unless the cam moved beyond its normal advance/retard arc because it's designed to work in the advanced and retarded positions.
Are the exhaust valves bent? If it was timed correctly they should be ok. If they are bent surely that points to incorrect timing?

[seanmau5]

What code did it throw? I'm currently working my way through a p000a code..

[3C4M Guy]

I could write thousands of words on the saga of the experiences with my 3.2L V6. I was getting check engine lights, limp home mode and a DTC for camshaft/crankshaft timing correlation. (00022 Crankshaft Position - Camshaft Position, Correlation Bank 1 Sensor A) The dealer analysed everything and diagnosed stretched timing chains plus the tensioner over-extended. I’ve since found out this is a common problem. The chains were replaced along with the main tensioner, two sprockets, engine rear oil seal plus other gaskets and bolts. There was no damage to valves or pistons.

5 months later, I had similar issues. This was diagnosed as an inlet cam adjuster with excessive free play, possibly the full 52 degrees of adjustment. Both adjusters had tested fine when the timing chains were replaced but one had now failed. So I agreed to replace both at a cost of $1,100 each for the part alone. Labour hours was the killer. The camshaft adjuster solenoids (also called valves) were in good condition and cost $500 each, so I accepted their advice that there’s no reason to change them. Both these jobs cost together cost many thousands of dollars. Again there was no damage to valves or pistons. However the dealer made a decision that from then on they would always replace the cam adjusters whenever they did the timing chains.

A couple of months later I had the same camshaft/crankshaft correlation error again. They concluded that one of the new cam adjusters (inlet again I think) had failed after only 2 months. They stripped the engine again and replaced the inlet cam adjuster. Fortunately the cam adjusters had been replaced by a dealer and VW offer both a parts and labour warranty. So this third job was done at no cost to me. If I'd gone to an independent garage, VW would have covered the part cost only under warranty. This is about the only time I've had work done at a dealer and I'm glad I did!

Your R36 is a 2010. It's probably around this time that VW realised they had a problem with timing chains on the 3.6 and 3.2 V6 engines and changed to a more reliable chains with a different part numbers. It's possible that later R36s did not have this problem, but many of the early ones did. My repairs were done in early 2015 and all of the critical parts had new part numbers.

Are you still having issues with the car Gonads00? Maybe the seller knew this would be an expensive repair and was happy to quit the car you bought at a low price? If this job is going to cost you $5K+, you could possibly source a used engine from a wrecker for less.

[Gonads00]

Hi 3C4M Guy. I finished up replacing both cam chains, both cam tensioners and all guides. The problem persisted and was found to be the inlet cam adjuster. This was also replaced at some cost as the gearbox was removed a second time. The really difficult part was that the dealer’s service manager admitted that the existing guides/chains/tensioners looked to be in really good condition. Could’ve saved me considerable cash in removing the gearbox a second time if I was notified that the tensioners/chains/guides were all good before putting it back together initially. If tensioners/guides/chains all look good it seems obvious that the problem lies elsewhere but hey-it’s all water under the bridge.

The car is running like it should, no check engine lights and I’m always left with a smile whenever I drive it. I’m a bit resentful that I replaced a heap of stuff that didn’t need to be replaced, only to have to pull it apart to fix the actual problem but I guess I should feel comfortable that the valve gear is top notch.

The saddest thing is that I’ve gotta sell the car. I love it to bits and it is sooooo much nicer in every way than my old WRX, yet still almost as quick. Fast cars that handle well have no right to be so comfortable and quiet. I know I’m gonna take a hit, but I’m also satisfied that I’ve fixed up something properly that might have been broken down for parts at a wreckers. It’s a beautiful bit of gear that I’d love to keep but the garage is not big enough.

I really appreciate the help I’ve received on here, especially your last reply. You were bang on with the issue and I wish I’d read it before I got everything sorted.

Keep an eye out for a cheap-ish black R36 wagon on Carsales.

Cheers,
Ben

[3C4M Guy]

Hi Ben. I'm glad you finally got your problems sorted. I had a similar feeling that my issue may have been just the inlet cam adjuster all along and suggested that to the dealer. They said definitely not - that they'd laid the new timing chain next to the old one and the old one had definitely stretched. I guess I believe it.

So sorry you have to sell your R36 after all that work. You clearly love it. If you parked it outside, it shouldn't rust in Orange? I'm sometimes tempted to upgrade my 3.2L to an R36, but then I think of all the work I put into it. Not sure if I could face doing it all again. Now if yours was Biscay Blue, I might be tempted. I'd know I wouldn't have to replace chains, tensioners and cam adjusters!

Cheers,
Guy

[Gonads00]

Cheers Guy! I don’t think I could bear parking it outside, especially being a black wagon. The clear coat would cop too much of a beating from the uv. I could maybe get a good car cover but I fear I’ll just create a breeding ground for mice.

I think I’ll feel better if it goes to an enthusiast who will look after it. My wife’s put a post up on an R36 owners Facebook page which is receiving some interest which looks promising.

Thanks again,
Ben