glweek

I have a 1997 HX with 180k on it and am getting a ping starting around 2100rpm with even the slightest load. The spark plugs are NGK ZFRF4-11 with an OEM distributer cap and NGK wires all replaced about 10k ago. Timing is set to 12* as indicated in my Haynes manual. The Timing was checked with the jumper installed causing the check engine light to stay on, idle at 670ish checked with a gun with perfect red mark indicated as well as OBD2 reader also showing exactly 12.0* between 667-677rpm.

Its been happening for a while, but not getting any worse. I also have possible piston slap, first start on cold mornings till the motor warms a little. I have but haven't gotten around to installing a new fuel filter and have a pressure checker but have not checked compression yet. EGR valve was cleaned about 10k ago as well. Been raining for a while and no garage so can't check the valves at the moment.

What else do i check?

Wankenstein

First..try running 93 octane for the next couple fill-ups.
Read: http://articles.chicagotribune.com/1...e-premium-fuel

This read may help: http://articles.orlandosentinel.com/...as-premium-gas

ezone

Does it rattle at maximum load too?
Got a recording of it?


I think with high mileage those engines would rattle main bearings at light load conditions, maybe that's what you hear?

D17VTECPOWER

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