finally i took out the prechamber, cleaned it and put it back in. No more leaking.
anybody who has the similar problem can contact me for any help, howere i will not be responsible for anykind of damage. i can share my experience.

To those who might be curious about these newer engines.
prechamber is one piece thing. thre ring is just a ring to hold the pm in place. injector screws in in thre PM itself.

the prechamber / injector threads are same as on the dodge caravan axle shaft. i used an axle shaft outer piece with slide hammer to pull PM out.
i think the threads on saab, mazda 626, nissan pulsar axle (possibly some honda's) are also same.

thank you everybody who helped and tried to help me.

a1jatt
a1jatt at yahoo dot com