[duyjy008]

I always wear seat belt so could not be the seat belt.

The sound is a rush dingdingding sound which sounds exactly like a metal alarm clock bell.

 

[duyjy008]

Thank you 97ToyCar,73sport,oldfirebird for your recommendation. I will check the exhaust and spark plug on weekend.

I have changed engine oil about 2 months ago. The spark plug is almost 2 years old now, I will change it too.

I will let you guys know how things are going.

 

[duyjy008]

Thanks "touringcamry" very helpful youtube videos.

Part of the problems has been solved! The groaning sound was due to oil leaking at two of the spark plug gasket.

I firstly decided to replace the spark plug by myself, I got 4 single electrodes spark plug from parts store but found later from the user manual that only twin electrode should be used. And also the spark plug socket I have is too big for the job. What the hell, I later returned the spark plugs to the store and asked a mechanic to replaced spark plug for me.

The first two spark plug looked fine, but the spark plug from cylinder 3 and 4 had oil on the thread. The white central electrode also became pink color. So the mechanic replaced all the spark plugs and tightened each gasket. I had a test drive, bingo, engine sounded much happier and smoother. However, I still hear DINGDINGDING sound once during a short test drive.

The mechanic then suggested it may be due to loosen parts in the exhaust. Well I doubt that as I did drive passed some uneven surface without hearing the DINGDINGDING.

I hope the DING sound will disappear soon after a little bit of driving and i will use higher octane fuel next filling up.