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Do my spark plugs need to be changed?

Do these spark plugs need to be changed? Having difficulty telling.

I’d change them according to the owners manual recommend interval. Use exactly the same brand and model number that came with the car new. You can’t tell by looks.

My opinion, if you go to the effort of removing them, install new ones. But, why were they removed ?

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2 of those have a bit more oil deposits on them than the other 2. Might be a good idea to check your oil level regularly.

Yep, now that they are out, put in new ones that exactly match original equipment.

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They were taken out because my car was shaking at idle and while driving. Thought it could be the spark plugs

The only way to completely eliminate plugs as a potential problem is to replace them.

Knowing the make model year miles would really help us.

Exactly. I’ve never gone through the trouble of removing plugs to inspect them. If I thought there was a problem with the plugs - I’d just remove and replace. Plugs are cheap…my time isn’t.

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If you have them out replace them . If you dont need the car , order them from Rock Auto . Even most iridium plugs are less than $8 a piece . The Champion iridiums im getting for our van are $4.61 a piece . Change them and you shouldnt have to worry about the plugs for 100K miles . Most guys dont look at them before the scheduled interval because they have made it such a PIA to get at them .

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Did the plugs cure the shaking at idle though? Just clarifying things a bit.

And as stated, you cannot tell by looking whether or not a plug is good. It may look brand new and yet misfire while under a load.

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