Pulled spark plugs and...

[Sonic dB]

They were white, with crusty material...blackened around the first ring of the threads. They were in there for last 22,000 miles.

Burning too hot right?

These were Bosch Platinums...and its been recommended to me by Pelican, to switch to Bosh Coppers.

Would the Bosch Coppers be more in the heat range for my car than the Platinums were...and respond to heat better?

[Sonic dB]

uh oh....very bad things. I did a search on white spark plugs and dont like what Im reading. Possible burned valve ?

I suspect my 02 sensor is on the fritz and needs replacing... would this be the cause for running so lean?

[1fastredsc]

White residue on a spark plug is the sign of ultra hot oxygen, meaning detonation. The difference in spark plug isn't the heat range but the fact that platinum doesn't conduct electricity worth a crap. What makes platinum desirable is that it's a self cleaning metal when heated up. Therefore they last hella long before needing to be changed. But for a smooth running happy engine, copper is the way to go (or if you can afford it, those silver or iridium plugs are nasty). And when an o2 sensor goes bad i was under the impression that the car will typically go rich, not lean, since the object of the o2 sensor is to lean out the car anyhow.

[Rick Lee]

Don't get too worried yet. How are your power band, gas mileage, flat spots? I wouldn't go with platinum on a 3.2 engine. There are lots of things to check - air flow meter, throttle switch, head temp. sensor, etc.

[Jdub]

Go with Bosch copper. You may have deposits on your plugs from gasoline additives - have you used any additives?

Replace the plugs and recheck after setting O2, timing, and whatnot.

John

[UTKarmann_Ghia]

This seems weird, but why is there a 1 star rating on your posts Sonic? I dont even know HOW you rate posts, but that seems kinda silly.

[dhoward]

Seems to me like the real signs of detonation are deposits melted on the insulator, with melting also apparent on the electrodes indicating excessive heat. Crusty white deposits are more likely the byproduct of additives. Modern gasoline doesn't lend itself well to the old science (art) of reading plugs.

[Bones]

Maybe you've only just got the car and hence haven't been able tp keep an eye on the service items but if not you should change your plugs at more frequent intervals whatever the diagnosis turns out to be.

[Early_S_Man]

White deposits are a sign of hot combustion temps, but not necessarily pre-ignition or detonation. Signs of additional damage would have to be present before the diagnosis of detonation or pre-ignition can be made!