Spark plugs are they still good?


when i bought my car i was told it would go 100,000 miles before a tune up was needed my tracker is 8 years old ,does this time factor indicate i need for tune up or only the 100,000 miles ?


My opinion is that one should not leave plugs in an engine for 70k miles, much less 100k.
This recommendation is done solely to promote a vehicle as being little or no maintenance and aid in sales.
There is usually a “severe service” disclaimer and this is what applies to cars in the real, non-Alice in Wonderland, world.

Leaving plugs in for extended periods can also corrode them to the cylinder heads.
Hopefully when the plugs come out they won’t bring all of the cylinder head threads with them. If they do, the price for replacing those plugs is going to go way up.


The meter ran out long ago. Any self-respecting spark plug would retire at 50,000 miles. The 100,000 miles figure is pretty much a best-world case guess.


There are two issues with plugs.

The first is the function of the plug. Most new platinum plugs can function for 100,000 miles. On occasion they will not.

The second issue is being able to remove the plugs. After 100,000 miles most are very difficult to remove and after eight years they will be difficult to remove no matter what the mileage.

If my car had plugs, I would replace them at about 50,000 miles. DIY plug replacement is easy and cheap. BTW I would also replace the plug wires OEM manufacturer, never the designer wires. Also I like to use OEM brand and model plugs.


DIY on plugs depends upon the car. On my 2002 Sienna, it is a major task to replace plugs with labor costs over $200.

I tried to have those things replaced three times. Each of the first two times, when I picked up the car, I was told, “We did not replace the plugs. They don’t need replacing until 120,000 miles.” No call; just refused to do the work. Finally, at 110,000 miles I told them I was doing a lot of driving, and they condescended to do it.


There must be something wrong with their hearing. It’s your vehicle and your money and your decision whether to change the plugs regardless of the mileage.

I’d be looking elsewhere to take my business.


Well, Honda was even recommending something just as dumb as leaving plugs in for a 100k miles, and that is recommending that valve adjustments not be performed on solid lifter engines until a 100k miles +.

Of course, no self respecting and knowledgeable tech would agree with this idiocy either because it can lead to these kind of problems:

Who woulda thought…


I would leave them until the 100k mark, or reasonably close to that figure. The early double platinum plugs had a reputation for corroding to the aluminum heads and being impossible to remove. Since then, all these long life plugs (possible exception of Bosch brand) have an anti-sieze plating that makes them easy to remove even after all those years.

If you use a brand that does not have that anti-sieze plating, then you can use an anti-sieze compound on the threads. Do not use the anti-sieze coating on a plug that has the anti-sieze plating though. The may not be compatible and it could do more harm.