Engine Pinging Or Not?

[cozmo]

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

[Saltrampen]

I had a pinging sound which I thought was valves, it mainly happened

when the revs swung up / down during gear changes.

Dealer thought it maybe camshaft pulleys...

When I found timing was spot on and fuel was Ok,

I listened carefully to engine and found that the noise was coming from

alternator belt, when I took it off, I found sandy gravel stuck in the

belt grooves. When the belt was replaced,noise went.

Obviously it was the sound of gravelly bits in the belt hitting pulleys.

When the "gravelly" belt has warmed up and under less load, the noise goes.

This may not solve your problem, but worth checking out as the noise is

exactly like having the timing out (pinging/pinking).

Also listen to water pumps and Power steering pumps, I have heard them make

slight pinging noises as well. (Some noises are normal, for instance when engine

heating up, expansion noises occasionally heard).

Saltrampen

[cozmo]

Thanks!

Sound is very very quiet and I thinnk that it is some sort of ping, maybe when you change the gear and press gas pedal engine is under load so ping may occur. The sound is now almost gone, it doesn't happen every time (maybe few times during half hour driving). Mechanic says that maybe we could !Removed! timing a little bit, but he thinks that no damage will be done, because pinging detonation is occuring under heavy load (going uphill, acceleretaion) and it will be louder and it will last much more (I hear it just for a split of second, it is barely noticable from inside, from outside also but sounds like a little ping). My alternator, water pump, and belts are OK, no strange sounds, no clicking from the engine, engine is very very stable and you don't know if it is working or not (I CANNOT believe that after 150.000 kilometers this engine is still quiet like the first day). Well, OK I have valve seals that are showing age (it is using oil a little bit) but this is normal for 15 years of driving, compression is normal, there is no smoke, engine is dry, oil is always very clean, fuel consumption is very LOW (below 7,5 liters per 100 KM in city, and 5 liters - that's little bit over one galon - on highway).

Or maybe it is the fuel (I've filled up with new fuel and sound is almost gone)...

Regards,

Ivan