Engine Noise? 1.6 Gas Engine Sounds Like Diesel

'I apologize for posting a question about a gasoline engine in the 'diesel mechanics' forum, but I assume someone here is knowledgeable about this as well.'

'For the past two days, my Golf IV 1.6 with 60,000 km (had a 60,000 km service about 2,000 km ago) has been making a sound similar to a diesel engine. The engine already has a deep and robust sound, but since Friday, the sound has noticeably changed. It's especially noticeable at idle, both inside the car and from the engine itself when the hood is open. It's difficult to describe, but it sounds like a knocking sound, like a diesel. It seems to be coming from the left side, near the timing belt, but I can't pinpoint the exact location. The rest of the engine just sounds too loud.'

Does anyone have any ideas about this symptom?

I will definitely go to the workshop next week, but I still have about 30 kilometers to drive to get there. Should I just leave the car where it is?

Sure, no problem. Here's the translation:

'Thank you in advance.'

Hello Andi,

Your problem description is unfortunately very brief and uninformative. Therefore, it is very difficult to make a remote diagnosis.

However, if we consider the worst-case scenario, namely that your engine is making a knocking or rattling sound, I would advise against driving it for another 30 kilometers. Otherwise, you might end up melting a hole in the bottom of the pistons!

Perhaps you could provide more specific details. Does the engine always experience knocking combustion, or only under high load and at low RPM (which is the typical range where knocking occurs in gasoline engines)?
Does it happen only temporarily or permanently? What type of fuel did you use?
Did you read the error codes? If so, what do they say?

Your engine code is probably AFT, right?

Regards,
Alex.

Hello,

I don't think he's ringing. When I hear the word 'ring,' I imagine something more dramatic; I think I would hear him if he were begging for mercy.

Was wäre im Klingelfall passiert? Valve missing?

You can clearly hear it at idle, i.e., without any load. When I rev the engine higher, the normal engine sound actually completely drowns out the noise.
'The problem is happening constantly. I filled the tank with regular premium gasoline. It's only a quarter full now, and I filled it completely two weeks ago. The noise started only two days ago, so it probably isn't related to the fuel.'

The error memory is empty. I noticed that the engine shows a 30% load at idle, is that normal? It seems quite high to me.

Oil level is correct, but the engine identification is NOT available.

It seems like the engine is also running unevenly. The RPM is steady, but when I put my hand on the air filter housing, I can feel it clearly. Then, the engine moves irregularly, almost 1 cm back and forth on the right side, kind of swaying.

How can you tell if an engine is only running on 3 cylinders? Is that possible? The performance seems to be there, though.

Hello Andi,

Well, that doesn't sound so bad!
Based on your description, I would tend to suspect a quiet ticking sound, such as that caused by a faulty hydraulic lifter.

By the way, what's the mileage on your engine?

I wouldn't suspect a misfire in one cylinder, because that would cause a dramatic loss of power!
But I would still suggest that you take a look at the spark plugs and assess their condition, as they can provide a lot of information.
Perhaps you will notice a noticeably different spark plug appearance in one cylinder compared to the others.

Regards,
Alex.

hello,

'There's definitely some ticking sounds coming from there, but it's always been like that. The ticking is more of a light, mechanical sound.'

The noise that bothers me is more of a low frequency, but it's really difficult to explain...

As mentioned above, the engine has just reached 60,000 kilometers. I'm going to the workshop tomorrow and will post an update here later.

andi

It seems like the engine is also running unevenly. The RPM is steady, but when I put my hand on the air filter housing, I can feel it clearly. Then, the engine moves irregularly, almost 1 cm back and forth on the right side, kind of swaying.

How can you tell if the engine is only running on 3 cylinders? Is that possible? The performance seems to be there, but .

Hi,

If it's more of a dull clattering sound, and the engine is moving, it could potentially be a defective rubber component in the engine mount, causing metal-on-metal contact.

Sure, here's the translation:

'Hello'
Jean.

Hello,

I just came from Freundlich's. Although it was quite noisy outside, they said they could hear it too, and immediately started working on it, specifically focusing on the belt system. Their assessment: the V-belt was too loose (it was sagging). The cause: the tensioner pulley is faulty. Apparently, there should be a plastic coating on the pulley where the belt runs, but that plastic seems to have broken off, so the belt is running on bare metal. According to them, it should be fixed by tomorrow afternoon.

Let's see what happens.


'Der schnelle braune Fuchs springt über den faulen Hund.'
ADDENDUM

I did a little research online, and it seems like this is a somewhat common problem. This is what it looks like for me:
http://www.wkill.de/photogallery/photo26003/killer01.jpg The tension spring crumbled.

And things could have turned out differently with a bit less luck:
http://www.wkill.de/photogallery/photo26003/killer06.jpg OUCH [/img]