Once again, I'm hearing a small sound. The paranoid person that I am, I am thinking about it rather than letting it go.

1. It is not related to warm up. Happens at operating temperature.
2. It does not seem related to gas. I have tried every 93 station I could find.
3. It is very intermittent. Highly doubtful I could demonstrate it to a dealer at will.
4. I have no modifications. Engine has been generally babied.
5. It happens after I've been off the throttle for a while (say on a downhill). When I get back on the throttle moderately, I hear a pinging/detonation like sound, but only once, almost a key clanging. If I get off the throttle and get back on again, I cannot reproduce it. If I had to guess, I'd say it's a one time ping - happens perhaps once per driving day. The conditions generating it are similar to the air gasp sound - but that requires higher speeds. Perhaps it's the 10% ethanol that's everywhere?

I'm tempted to
a. try an octane booster (no idea what it does if anything)
b. techron injector cleaner
c. keep changing gas stations and cursing the unavoidable 10% ethanol

It's not a huge, huge deal. If I'm not sure that I can reproduce it, it must not be the end of the world. What stresses me is that I'm on the list for the software/plenum mod... I may want to get this resolved first.


It is not the same sound that I started a thread on a year ago. That really was a very minor exhaust rattle:
slight sound from engine

If for arguments sake, if it is a ping(knock) then the ECU will retard the timing straight away which is why it would not happen for some time after.

Yes, 4x4, that would be consistent wouldn't it? I guess I'm wondering if anyone else is getting this sound. I'm buying gas (only 93) in NNJ. I've tried Shell, Sunoco, BP.

To clarify, the air gasp sound may require a quicker but similarly moderate application of throttle. Most audible in 4th & 5th, perhaps due to airflow? You can literally hear the engine suck air in. Lovely, soulful car.

This rare ping if it is a ping, is annoying me though.

I get it too, I have always gotten it. 94 Octane makes no difference. I am not 100% sure it is pinging. I will post the question in the Tech Section.

__________________
Tomasz

Apologies for spelling mistakes, most of them are keyboarding errors. To enjoy this forum I run out of time to proof read.

I don't believe I have heard it, but wasn't listening for it either. Of course it will never hurt to bring it into the dealer for a read out of any codes from the ECU and a fresh reset of the ECU. Solves some little things sometimes.

Consider this thread closed, we're continuing at

Engine pinging.