Engine pinging or not?

[cozmo_im]

Hello to all!

I know how the engine pinging sounds, but either my pinging is strange either I am crazy.
I hear this sound for a split second (it sounds like ping or valve chatter) only when I change the gear from 2nd to 3rd and from 3rd to 4th gear (I have an EE90 Japanese Corolla, 2E engine).
I've tried my engine under heavy load - I've tried to go uphill in 3rd gear almost from start and there is no pinging, also on acceleration and under extreme speeding (when pinging should occur) there is no pinging. Only when I release clutch pedal and press gas pedal. And only for a split second. Remember, it does sound like pinging (or valves chatter). Clutch is working fine, no strange sounds, gears are OK... engine is in very good condition...

What is it? Does anybody knows?

Regards to all,

Ivan

[Big Chaze]

Originally posted by cozmo_im
Hello to all!

I know how the engine pinging sounds, but either my pinging is strange either I am crazy.
I hear this sound for a split second (it sounds like ping or valve chatter) only when I change the gear from 2nd to 3rd and from 3rd to 4th gear (I have an EE90 Japanese Corolla, 2E engine).
I've tried my engine under heavy load - I've tried to go uphill in 3rd gear almost from start and there is no pinging, also on acceleration and under extreme speeding (when pinging should occur) there is no pinging. Only when I release clutch pedal and press gas pedal. And only for a split second. Remember, it does sound like pinging (or valves chatter). Clutch is working fine, no strange sounds, gears are OK... engine is in very good condition...

What is it? Does anybody knows?

Regards to all,

Ivan

What grade fuel do you use???

[cozmo_im]

Originally posted by Big Chaze
What grade fuel do you use???

My car is carburetor type so I don't have the catalysator. I use super 95 or super 98. There is slight difference, car will run little bit better on 98 octane. But even with 98 I hear this sound. It is not so audiable, it is barely heard from inside the car and it lasts a split of second. But it does sound like a pinging. I asked my mechanic he says that maybe we can retard the timing little bit, but this is not detonation type pinging - I never heard pinging during hard acceleration or going uphill or something like that. And it is not so loud and it lasts split of a second, only when I press the gas after changing gear. And it doesn't happen always.

I will retard timing little bit just to be sure.

regards