How Many Miles on This Spark Plug??

[Yokopup]

I bought my '01 LTD about a year and a half ago with 110K on the ticker. I got around to changing the spark plugs today ( it has 120K miles) and I was suprised at how worn they were. I thought that the Sequoias had the 100K platinum plugs installed from the factory (like my '00 Accord does) but of course I was wrong. The plugs that were in there were the OEM Denso K20R-U's. I know they were in there for a while because they were difficult to get out and 'CREAKED' when they broke loose. I was nervous as a cat pulling these things out hoping I wouldn't break one off in the head.

Anyway, check out the pic. How many miles do you think are on this plug? I find it hard to believe that these are the factory originals, but they were hard to get out. The gap for the plug in the pic is .058--about average for the other 7(spec=.031). I'm surprised that the truck ran as well as it did.

As a side note, I HATE it when people do not use never-sieze when they change their plugs....

Jim

[JBH1989]

They don't use plats in these, in fact my owner's manual said to change at 30k.

K20RUs are basic copper core $1.99 plugs.

The high energy electronic ignition could compensate for that gap pretty well, they produce a ton of voltage and it doesn't require much to run under normal conditions. It was placing more stress on your coils though. Good thing you changed it out before required voltage began to exceed max coil output voltage and you started misfiring.

[apurazzo]

they look like the factory originals i just changed mine at 50,000 miles and they looked way better

[speed25]

Sure, they look worn, but I'm not surprised at all that it still ran smooth. I'm not saying they shouldn't be changed, but people do tend to put too much emphasis in changing out plugs regularly. Even in aircraft engines the usual deal is remove, clean, reinstall (of course they have two per cylinder).

Cheap and easy enough to do though, so no real problem in "overchanging."

[trd sequoia]

If you didn't change them allready you can put platinm plugs in. The dealer should have conversion chart. Then no worries for awhile.

[JBH1989]

Originally Posted by trd sequoia

If you didn't change them allready you can put platinm plugs in. The dealer should have conversion chart. Then no worries for awhile.

The problem with that mentality is that people will leave 100k spark plugs in the engine for 100k miles. That is not good, very easy to screw up the head when someone leaves them that long.

[Yokopup]

Originally Posted by JBH1989

The problem with that mentality is that people will leave 100k spark plugs in the engine for 100k miles. That is not good, very easy to screw up the head when someone leaves them that long.

I feel the same way. FWIW, I went ahead and put some NGK V-power's in there (they didn't have the Densos' in stock) and used never-sieze on the threads. The NGK's are just normal resistor type plugs that will need to be changed at around 30K-40K. I know that the plugs will be easy to change when the time comes, and I will have no worries about getting them out. I will probably be able to change them all in about 30-40 minutes. Easy. That's something I don't mind doing at all.

But man, I gotta tell you, I was sweatin' bullets getting those Densos out. I assume the heads are Aluminium?? I was really scared of stripping one of the ports out. I had visions of multiple, multiple $100 dollar bills floating away... I got lucky because thay all came out OK and the new ones went in like they were supposed to.



Take care,

Jim

[JBH1989]

I personally think the risk is a little overstated. I've pulled plugs out of an X5 with 135,000 on them that still say "BMW" and it doesn't take much to get them out. Sure aluminum isn't as strong as cast iron, but it's not like we're working with soda cans here. Little 3/8" impact on low makes quick work of plugs, even stubborn ones.