Spark plugs - Replace or not ???

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My 2004 Saturn Vue 3.5 L hits 100K miles last week. The owner manual calls for spark plugs replacement. I removed one in the front this morning. The OEM is Denso iridium with platinum ground pad and it looks perfect, the gap remains the original gap (040).

Shall I replace the spark plugs even I think the car will run an other 100K with this original set ???
 
Do it. If for no other reason than they might get welded in if they stay longer.
 
I would replace all the plugs at the recommend interval (100K) just to be on the safe side. If all the old plugs look the same, you got a bargain on the OEM plugs, they all might go another 10K), but there's a reason the original maintenance interval was established.
 
I'll go against the grain and say keep the originals. If they are within spec, have considerable amount of electrode left and look good, why shell out for shinier ones? Iridiums are expensive, and do last a good long time.
 
I will say replace them. Also, I will add this. Take your time and find the plug you want for cheap online - or - if you like to shop in a store locally, buy them when it fits your schedule and is convenient for you. This way you will have the replacement set on hand. Then you can put them in when time allows. This will give you some more miles out of your OEM plugs.

When you do replace them please post pics of the old ones.
 
Waste of money. My 2000 Intrepid has the original Champion Plats in there . 137,000 miles.I inspected and cleaned them in the spring and reinstalled with some anti-seize on the threads. The car gets the same mileage as when new.
 
Swap them out, as per the manual
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Platinum of one side, and iridium on the other?
Seems strange to me.
Sounds like you could go another 50k with those plugs, but check all of them first.
At a minimum, it is good to get them out and loose a this point so they will not stick in the future.
 
Mechtech2:
On the ground end I see a small pad, I guess it is platinum material to prevent erode. The electrode is iridium.

The 100K plugs looks perfect to me, the color at the tip is normal light gray.

Thanks for the suggestion.
 
Plugs are cheap and easy...just change them.

I changed mine a little after 80K. They were pretty worn, with big gaps, but my truck has burned a lot of ethanol which is apparently hard on spark plugs.
 
Like a few others have mentioned. It is not good to leave plugs in the engine for many years if you expect to get them out, especially if they have not been installed with copper antiseize...I'd replace them if for no other reason then to keep the plugs from seizing in the head.
 
Originally Posted By: winter55
My 2004 Saturn Vue 3.5 L hits 100K miles last week. The owner manual calls for spark plugs replacement. I removed one in the front this morning. The OEM is Denso iridium with platinum ground pad and it looks perfect, the gap remains the original gap (040).

Shall I replace the spark plugs even I think the car will run an other 100K with this original set ???



I would replace them regardless of how they appeared. Also, you do not gap Iridium plugs as it damages the Iridium coating/layer. So, if you checked the gap to determine the OE gap is still there you have probably damaged that plug.
 
The spark plug recommendation is based on a hypothetical duty cycle. If you're duty cycle is different (guaranteed) then your mileage will vary.

It's entirely possible that the plugs are fine for many more miles at your usage level.
 
winter - Hopefully you have a little pad on BOTH the center and side electrodes. They can be quite small. Usually, they are either both platinum or both iridium.
 
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