ticking sound is gone...

[pong]

there was this weird ticking sound coming from the engine... dunno
what it is...

then... weeks after this... i noticed my air cleaner was so dirty so i removed
it... didnt have an air cleaner for a few days...

the sound was totally gone and the power was back...
after putting a new air cleaner... there is a slight ticking again and
there seems to be a decrease in power.

what could be the problem? lack of airflow? how do i fix it?

thanks!

(525i m20 1990)

[632 Regal]

I highly doubt a lack of power, the clacking could be a leaky intake gasket etc.

there was this weird ticking sound coming from the engine... dunno
what it is...

then... weeks after this... i noticed my air cleaner was so dirty so i removed
it... didnt have an air cleaner for a few days...

the sound was totally gone and the power was back...
after putting a new air cleaner... there is a slight ticking again and
there seems to be a decrease in power.

what could be the problem? lack of airflow? how do i fix it?

thanks!

(525i m20 1990)