Engine Clicking Noise: Causes & Solutions (Solution)

Hello,

"For the past two days, I've been experiencing a speed-dependent clicking noise in my Audi A6 3.0 ASN. It started with a whistling/howling sound, which to me sounded like a bearing issue on the ribbed belt."
With the next time I started the car, the noise/clacking sound appeared. The engine seems to have power (maybe not fully, I didn't want to push it too hard).
After a few kilometers, it started displaying error messages indicating misfires for the entire bank 1 (driver's side cylinders 1, 2, and 3).

I have now removed the serpentine belt, but without success.
I once set the timing belt to Top Dead Center (TDC) and managed to position the crankshaft and the second bank correctly, but the first bank is misaligned (likely by one tooth).

"At the same time, I've been experiencing an intermittent error in the control unit for some time now."
16399 - Bank 1; Camshaft timing advance; Exhaust.
P0015 - 002 - Target not reached - Warning light ON.

The error appears occasionally. I assumed that the variable valve timing system might be faulty.

The question now is whether adjusting the device by one tooth could cause such a noise?

Approximately 7000 km ago, the timing belt jumped a tooth, but it was on the second bank of cylinders. In that case, it was four teeth. However, after replacing it and properly aligning it, everything worked again. (The previous owner replaced the timing belt at 140,000 km, but I don't know if it was installed incorrectly or if there was a material defect).


The car now has approximately 142,000 kilometers on it.

I also made a video with the sound, but unfortunately I can't attach .mov files here.

Is the water pump in good condition or has it been replaced? Also, is the tensioner pulley (driver's side) properly adjusted?

Error found. The wheel on the water pump had completely disintegrated (on the belt side).
It has also been replaced by me before (with all genuine Audi parts...).

Since I already had everything open, I figured I might as well tackle the camshaft adjuster at the same time.
You should loosen the screws on the camshaft while they are held in place by the adjustment tool. This worked on three other vehicles, but the last screw won't come loose. The camshaft is starting to rotate within the tool.
"Does anyone have any ideas on how to remove it? I was just thinking about using an impact driver..."

What about the camshaft adjuster? Do you only replace the wheel itself, or also the control housing?

Thank you very much!

Quote:

I would only have thought of the impact wrench...

Exercise caution and turn the relevant cylinder row away from Top Dead Center (TDC) to avoid damaging the valves.

Quote:

What about the camshaft adjuster? Do you only replace the wheel itself, or also the control housing?

"That's a good question. In theory, it would make sense that if the camshaft timing is adjusted, the knock sensor wouldn't be able to reach its target value – or perhaps it isn't actually defective."

It's also possible that the control system for the northwest adjuster is not working correctly.
Since these tend to fail frequently in the 3.0 models, the question is what parts people have replaced in theirs.



I left the special tool installed, so nothing should happen now...

Thank you!

If you're going to do it, you might as well replace the other side at the same time.
Including everything, it would be approximately €400 for the control housings and another €400 for the wheels.
or you can use the money to go on vacation.

I would inspect it and only replace it if it is 100% defective. Possibly, I would also replace the seals and O-rings.

I'm more interested in the question of why the Wapu project was abandoned so quickly.
Something seemed to be wrong there...

I once asked a mechanic near the .
He also said that you shouldn't buy anything there at all. It's true that it would be a lot of work to reassemble everything if the part is actually defective, but since I'm doing it myself, the costs should remain manageable.

He also mentioned that usually only the wheel itself is broken, and not the casing.

I just need to swap the valves from left to right; usually, that's where the problem lies. And you can replace them without having to remove the timing belt later.

I'm now waiting for the parts to arrive tomorrow morning and hoping that I can get the engine running again with them.

Unfortunately, I don't know what's going on with the WAPU. You buy the original parts to avoid having problems...

Thank you very much for the answers so far!

cksIT wrote:

I'm afraid I don't know what's wrong with the WAPU either. You buy the original parts so you won't have any problems.

For my part, I have decided not to install any more VW/Audi water pumps. After now having experienced 5 units of different engine types fail shortly after being replaced – specifically: becoming very noisy, developing excessive bearing play, completely disintegrating, leaking at the coolant pipe connection, or failing to seal properly on the engine block, which again meant a return trip to the and further discussion.

Here are the vehicles:
- Skoda Octavia 1U2 1.6 101HP - bearing failed after 3100 km.
- In a Lupo 1.4 TDI AMF engine, the bearing failed and started leaking after only 1800 km.
- Two Audi V6 engines (2.8 30V and 2.7T), both with leaks at the engine block -> warped sealing surface.
- Golf 4 1.9 TDI AHU: After 4200 km, the bearings were worn out and the timing belt failed.

On all the pumps from , there was a sticker that said "reassembled in Malaysia".
...what's that supposed to mean? After all, you can't get those at a bargain price.

I've always used SKF parts before, and now the vehicles are running smoothly, except for the AHU engine, which was faulty.
The sealing surfaces of the SKF parts are machined, they have good bearings and seals, and the pump impellers also stay securely in place; definitely worth the extra cost for the 10-series version.

Regards,
Mpire

Quote:

I have personally decided not to install any more VW/Audi water pumps. After 5 units of different engine types failed shortly after being replaced – specifically: they became very noisy, had excessive bearing play, completely disintegrated, started leaking on the weekend, or could not be sealed properly at the block, which again led to a return trip and discussion.

I strongly disagree with that.

Of the countless "original VW replacement water pumps" (the ones with the "X") that I have installed so far, not a single one has failed prematurely or before the next timing belt change interval.

Either you were sold cheap imitations, or someone tightened the tourniquet so much that the doctor had to come. That's definitely not standard procedure.

That doesn't mean there aren't equally good or even better pumps available on the open market.
You just have to find them.

I'm not so sure about those being counterfeit; they were installed directly by the contracted workshop, and they were properly mounted.
Only the Lupo with AMF is my own vehicle, which received a replacement pump from me. The others were previously all at .
Regarding the tension, I have to agree with you; too much tension can damage the rollers and the pump .



Mpire.

Hello,

Just wanted to let you know that the system is working again.

The camshaft wheel (with the adjuster) on the exhaust side was defective.
After the replacement, it's running as it should again. It still shows a high value for the exhaust side in the main control unit (ECU), but since that's a learning value, it will likely decrease over the next few days.

Thank you for your help!

Thank you for the feedback .