Engine Ping - mechanic recommended SeaFoam

Did you check the gaps? Hard to tell if the centre posts are eroded or coated. It does like the gaps are a bit big. This is the spec from 2007 Owner's Manual (closest year I happened to have):

 

Should be ok IMHO, but stick with the premium gas to avoid the ping to your get it done.

Edit, over here in UK we call it pinking. Something to do with the sound it makes rather than the color (colour) ok?

 

One should NOT try to alter the gap on a platinum or iridium spark plug.
They come gaped from the factory.

 

Did not know that. Thanks, the old ways are not always the right ways today.

 

Give the computer time to adjust

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I think it depends on mileage. Someone else may know more about that part. Make sure its Top Tier gas as well.

Mine didn't need plugs but when I had Toyota do the fuel system cleaning on mine last week and I already had E0 BP gas in it, my mpg went up 3-4 mpg.

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I am using BP E0 89 octane....cheaper than 87 at other BPs. Go figure. Like, 40 cents per gallon cheaper.

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And you need to tell us the REST of the story.
Like what octane gas are you using with the new plugs.

I think you need to visit a DIFFERENT mechanic because this noise you are hearing might NOT be simple detonation ping.

A "decarbonizing" procedure probably won't hurt anything if done right.......but I suspect that it won't help either.

Sometimes small noises appear in older engines and the cause isn't always easy to identify.

 

OK, so you have a decision to make:
Either do a "de-carbon" in an attempt to fix the problem.....OR......start using a higher octane fuel.....OR.....start shopping for a new car.
Or maybe just live with it.
Top Tier and ethanol have no bearing on your present problem.

 

So a few decades ago, BMW and Mercedes realized there could be SIGNIFICANT differences in "octane" between two fuels with the same Pup Octane number. It is more than possible that due to age, wear and a multitude of other conditions that cannot be accurately measured, the Pump Octane you have is simply sub-optimal for your engine. Switching brands in the US can alleviate this in some cases.

Why? Pump Octane is nothing more than the AVERAGE of Motor Octane and Research Octane - have you ever noticed the 87 = (R+M)/2 printed on the pumps? yup, that's what it means, the AVERAGE of the two. Maybe your common brand (or mix) has a relatively high Research but a low Motor octane -> The AVERAGE could still be 87.

For motor vehicles, not race cars etc, Motor Octane is often, but not always the more important. Guess what, ethanol is highest in Research octane and it degrades over time and moisture.

USDM cars have knock sensors that monitor for "pinking" and adjust timing accordingly, within certain limits. Given your ECU cannot adjust enough, my guess is that the AMM/MAF is dirty causing more air to enter than the engine thinks. Combine that with a old and tired WBO2 and you have "pinking".

I don't think you are in any real danger of hurting the engine. Ford tests ALL their engines for nearly 40Hr of continuous HARD KNOCKING and will not approve the design unless it can pass the test, I doubt Toyota are slackers in this measure.

 

BUT......the truth IS that you don't really know what it is until you fix it.

All the evidence points to a pre-ignition ping because the "premium" gas seems to fix it.
But there is a tiny little chance that the noise is something else.

At the very least, if you can get rid of it by using a higher octane gas you SHOULD DO THAT.
Over a long period of time, whatever is causing the noise might do some damage too.

 

Best bet take it to Toyota and see what they say.

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