Alright guys ive have done my research on iridium plugs and my car has over 100k on it. Im scared they havent been changes because when i bought the car the air filter was almost totally cloged. So i am changin the spark plugs and from what i hear the iridium is a lil better. I want to know from experiences if they are better, or can expect to see gains if my plugs that are currently in there are bad or really used? If my current plugs are alright will they work any better or more efficiently. Thx guys

 

Iridium plugs are excellent. At 100K, most likely they've lost their edge and the electrodes have likely eroded considerably by now. This erosion causes the gap to widen between the two points of the spark, requiring more voltage to arc across. This means that you might not be burning your fuel very efficiently. You should see improved mpg after you change them, that is, if they are the originals.

One thing to look for while you're changing the plug, there have been some reports of oil pooling on some of the plugs. If you don't see oil, look at the plug threads to be sure there isn't any there either.

here's the thread on the oil pooling:


https://g35driver.com/forums/g35-sed...rranty-up.html

 

Alright thx a bunch