I just changed my spark plugs after 6 years and 103K miles of usage but after doing it I wish would not have waited so long.

Does it look like normal wear on the old ones? I'm no mechanic so I don't know what to look for exactly.

Old vs. New:



All 4, different angles:

 

They look just the way they should. Nice even grey/brown color, and all the same shade (more or less). Gaps look kind of big, but that could be the picture.

 

The spark plugs appear to be in the expected condition for 100k. It looks like the gaps opened up about .16mm. This is common in high mileage plugs as well.

In the best interest of efficiency, power and overall maintenance, I change plugs after 50k. 100k is just to long of an interval.

 

The gap is due to electrode wear, which is expected after 100K. I prefer to change my plugs out during the 60K service.

 

This reminds me of the "always change your oil every 3K miles" discussion. I changed the plugs on schedule in both my 05 and 07 (at around 105K miles for both, and again at 200K in the 07), and perhaps because of all highway miles, the old ones were in good shape. I've never noticed any change (better or worse) in performance or fuel mileage after the change, so I'm confident that the recommended interval is probably appropriate. But like changing the oil, and ATF, and who knows what else, if doing it more often than necessary makes you feel better, than by all means pony up.

 

I always had a shudder until the engine warmed. Lots of head scratching. Replaced plugs around 50k and problem took care of itself. TSX Sport Wagon. Just sayin.

 

Hi there, new member and first post. Not sure if this thread is considered correct for my question....

I'm due for spark plug replacement and was hoping to come across a DIY for 2009 TSX tech. Forum/google/youtube search came up with DIY for first gen, and IM not sure if replacement method is the same for 2nd gen. Could anyone confirm if replacement method is the same 1st gen vs 2nd gen. If not, any leads or DIY instructions would be greatly appreciated!

 

pretty much standard for the 4 cylinder engine. Key thing is to be really careful not to strip the threads and not to over tighten them.

Suggest to do it with someone that had done it before.

 

+1 on the above.
100K miles for plugs? Too long imho. You can buy a 4 pack of NGK on ebay for $30.00 and replace in under 30 minutes.

 

Same as most others...40K or 50K change has been my normal plug change interval on any of my cars.