Headaches: Causes, Treatment & Relief

Hi everyone,

Actually, I'm quite happy with my 1.9 AFN engine if it weren't for the constant technical problems that come with the TDI version!

This car now has 130,000 km on the odometer. I've had to take the cylinder head off twice: first because of a defective timing belt tensioner (which bent 4 exhaust valves), and then shortly after (just 8,000 km later *laughs*) because I was experiencing extremely high oil consumption (due to worn piston rings *lol*).

Okay, everything seems to be working fine again after about 14,000 kilometers.
However, recently, and as they say, good things come in threes, I've noticed a clicking sound.
In my opinion, it's caused by the valve timing system, which occurs during high-speed operation at a lively 4000 RPM. It can be heard both when the engine is cold and warm. However, it's not noticeable under partial or full load because the combustion process masks the rattling sound.

Some of my friends think I'm listening to...

Unfortunately, so far I've only had one 1Z engine with 280,000 km (approximately 174,000 miles) that runs much smoother than mine.
Test run. During the test, no rattling sounds were audible at high speeds.


My guess is:

Due to the modification of the four valves, the valve seat was reworked to such an extent that at high speeds during the power stroke, the valve hits its seat so quickly and forcefully that it makes noise.

or

The hydraulic lifters were unable to compensate for the valve clearance during the tours.


Now, my question is:

Would you spend almost €800 on an original AT head hoping to get rid of the rattling noise?
or generally speaking, would you start working on it?


P.S. Personally, I already find it a bit annoying, even though I used to have a vehicle that rattled and clunked much worse. However, that car had good performance, and on top of that, it didn't have any HV (High Voltage) components!

Hello,

Did you measure the dimensions of the fan bearing after replacing the fan?

Hello,

Since your next step is probably going to be an engine swap anyway, I would continue using the current one. Either it will last, or it won't. If it doesn't, at most the entire engine block will fail. Given that it already has 130,000 km (approximately 80,000 miles), I would be willing to take that risk.

Best regards,
Christian.

@g1om:

Quote:

...it occurs at lively 4000 RPM. It is audible both in cold and warm conditions...

I hope you didn't mean 4000 RPM and a cold engine, right?
Then I wouldn't be surprised if your engine is already nearing its wear limit with that mileage and if you start experiencing problems constantly.

Regards,
Alex.

Thank you for your contributions.

I would like to add that the engine, including the pistons and block, are in excellent condition. I was surprised myself when I checked the piston measurements; they are within the specifications for new parts. Regarding the valve guides, it should be mentioned that these were also replaced during the valve replacement. Well, 4000 RPM with a cold engine is certainly not ideal, but as long as it's not under load, nothing will happen to it even after 300,000 km. There are definitely some motor experts who think you shouldn't rev the engine above 1500 RPM when it's cold, or have similar ideas; however, they then drive in a certain range and floor it .
or maybe run it for half an hour at idle until it warms up *lol*
'Those are likely the first ones that will need a new camshaft.'

Well, maybe I'll just stick with what I have and avoid those high speeds, or simply turn up the music louder.

Sure, here's the translation:

'Thanks again.'