When should spark plugs be changed?

Question

I have a 1995 chevy lumina with 156,000 miles on it. The spark plugs were last changed 4 years ago with 114,000 miles on it. I don't notice my gas mileage going down at all. I drove mostly highway miles. Does it sound like I should change these plugs at this point or should I be good for a while yet?

Answer 1

If they are copper plugs they should last 15K in good running conditions (no misfiring or anything). If they are platinum they can last 60K and some plugs have even lower service intervals like Bosch IR Fusions which have 4 prongs so that every time they spark they fire from the least resistant one (leading to a distibuted wear so they last 100K miles or more as far as I've heard) though I've also heard Bosch's quality control is below NGK and a couple of other brands though these may be biased as a lot of these same people say they've never had them but to check out this one same dude on cardomain.com that got one bad set of Bosch Platinum +4s.

All in all I'd probably check what OEM plugs are. If the factory uses ACDelcos, use ACDelcos in the correct heat range.

Answer 2

The old saying is : if it ain't broke then don't fix it. You are due a minor tune if the plugs are that old but replace with the same type brand and heat range. Normally they'll last 100k. Sometimes longer? Just watch the fuel mileage and replace them when you lose a few mpg and air filter service doesn't bring it back up.

Answer 3

a tuneup with spark plugs changed should be done every 1 or 2 years.  usually youll notice that your car takes a long time to start is when youll need new spark plugs

Answer 4

I change mine every year(12000mi).   They do wear out. and you do lose on perfomance.

Answer 5

some plugs are made for thirty thousand miles and some are 100,000 (platinum) if you pull one out platinum plugs are pointier than a regular plug and sometimes say platinum you can call a parts store and give them the number on the plug and they will be able to tell you

Answer 6

The 95' Lumina with 3.1 V6 uses a Resistor type spark plug that Chevrolet recommends changing at 30k mile intervals.  A quick read of the maintenance schedule in your owners manual will confirm this.

Answer 7

they should be good for 100k again

Answer 8

check your book.  most newer cars only require once every 100,000 miles.  traditionally they should have been done every 30K, but that's not usually necessary anymore.

Answer 9

I change mine twice a year. Once in the spring, once in the fall.

It's cheap. And always does me good.

Pull one out and look at it. You will know deep, deep, deep down in your squishy insides if it needs replacing.

If you're having a hard time spending the $16.00 on a new set, then you might squeak when you walk.

Your car will thank you.

Answer 10

Every 1000 miles