Engine Misfire, Ticking, and Noises.

Hello,

'On my car, with 183,000 km on the odometer, the timing belt was replaced at 180,000 km. After that, the engine ran great and very smoothly! However, since I do a lot of highway driving and recently drove a long distance, I've noticed a constant ticking or clicking sound. When the engine is cold, you can hear this quite loud clicking very clearly. As it reaches its operating temperature, the noise becomes quieter, but it's still audible.'

Overall, I have the impression that the engine is running roughly and noisily.
The performance and torque are okay so far! Could it be that the settings, such as the injection timing, have been adjusted again?

I didn't find much using the search function.
Thank you for helpful answers.
Best, Boro.

How does the ticking sound exactly? Is it speed-dependent? Is it only audible when idling, and does it disappear after a short burst of acceleration?

Hmm, it's similar to the sound you hear during a cold start, when the oil is being pumped up! Except that this sound doesn't go away...

'I topped up the oil before starting, but it still made the noise! It gets quieter as the operating temperature increases, but it's still audible. You can hear it across the entire RPM range, but around 2000 RPM the engine noise becomes too loud to hear it.'

The fuel injectors were replaced at 152,000 km.

Hello Boro,

Sounds are difficult to identify accurately through a forum.

If the clicking sound you hear only lasts for a few seconds after a cold start, the hydraulic lifters are likely the cause.
As long as there's nothing clicking persistently, I wouldn't do anything in this case.
An oil change (even to a different oil brand/viscosity) can solve the problem.

Best regards, Rainer.