Spark Plug Extended Change

[S2000driver]

OK, so I was wondering, what if you let your spark plugs go 45,000 miles instead of the recommended 30,000? Whenever I change my NGK on my Hondas (for instance, my CR-V... the S2000 has platinum) the old plug looks great and still has a good gap.

[ February 17, 2003, 07:53 PM: Message edited by: S2000driver ]

 

[joee12]

S2000Driver, I think that it depends on the vehicle. The non-platinum NGKs(can't use platinum plugs on the LS motor) plugs in my Acura Integra look good after 30,000 miles, but on my 3.0 Mazda, the platinum Motorcrafts from the factory looked like crap after 32,000 miles. I also changed the platinum plugs on my sister's Rodeo last week, and they looked pretty rough at 60,000 miles. I still do not think that I would ever let platinum plugs go the recommended 100,000 mile change interval. -Joe

 

[Patman]

Honda's 4 cylinder engines are so easy to change plugs on though that you could do them once a week and barely break a sweat. I can do my wife's plugs in under 10 minutes, and that includes the time it takes me to super scrub my hands when I'm done.

 

[JonS]

Patman
My wife has an inline 4 cylinder Nissan. The plug wires and plugs are on the very top of the engine. But they have different plug wires than i have always worked with. How do they come off? They go into the valve cover. The garages want anywhere from $89.00 to $189.00 (Platnum)just to change the plugs. I feel like i could change them but have never used these plug wires. I don't want to break anything.

 

[sprintman]

Use NGK Iridiums (better than Platinums) in both vehicles. Fit n' forget for 100,000kms+

 

[TheLoneRanger]

Sparkplugs rarely wear out. The plug mfgs just want you to think they do. They do require maintenence though. Remove them at 30k mile intervals, clean, regap, sharpen the electrodes, and check with an ohmmeter. If resistance is over 2K ohms, then replace them.

I once ran a set of Motorcrafts for 125K miles using this procedure. The car still had the original factory plugs in it when I sold it, and ran great......

 

[Rick in PA]

The one thing I've heard that can be a problem with super long extended sparkplug change intervals is the plugs seizing in the heads. I've used anti-seize on the plug threads last time I installed a set. Just be carefull not to get any on the insulator, it could short out the plug.

 

[UncleS2]

I ran the factory spark plugs(Champion copper-cores, RC9YC) & wires in my Neon for 89,988 miles. They were pulled & gap checked at ~30 K miles, that's all. When removed, on general principles, the car still started, & ran fine, no misfires until ~6350 rpm. So, will it hurt to run your plugs an extra(measly!) 15,000 miles? I say if it runs OK, the plugs are OK enough. My owner's manual recommended plug change at 30,000 miles, I think.

 

[tadaima]

Cleaning / Gapping your plugs and running them over the service intervals (ie 30K) is all right. Depending on what kind of plugs you are using. For the cheap Autolite copper plugs, why not just buy new ones. It will probably save you the time in cleaning them, and worrying about getting the tips dirty with grease or oil from your fingers.

If you're talking about your standard platinums (which you paid $$ for), I think it's worth spending the time to clean and regap them.

 

[Patman]

quote:

---

Originally posted by sprintman:
Use NGK Iridiums (better than Platinums) in both vehicles. Fit n' forget for 100,000kms+

---

I've always been under the impression that iridium plugs won't last as long as platinum, but longer than copper. So they are probably good to 50,000 miles but not much more. I wouldn't leave platinum in for 100,000 miles. My stock platinums in my Firebird were completely toast by 60,000 miles. They should've been changed at 30-40k (I didn't own it then though)

 

[Whimsey]

I have a '96 Ford Contour w/2.0L 4 cyl Ztec and just changed the factory plugs @ 52,000 mi. The factory change interval was 60,000 mi. I changed them early because I'm going on a long trip and it was convenient to do them now. The factory plugs were single platinum, with the platinum tip being on the ground or center electrode depending upon which cylinder it was in. The replacement plugs are double platinum plugs. Upon removing the original factory plugs they were in good shape but the platinum tips on the plugs with the platinum on the ground electrode were worn down. Probably more important was installing the new plugs with anti-seize on the threads. If you leave the old plugs in the aluminum head for an extended time period you probably stand a good chance of stripping the threads upon removal.

Whimsey

 

[Patman]

That's another good point Whimsey!

And you reminded me, one of my plugs in my car is still original, we couldn't get it out. One of these days I'm gonna have to get my friend back over to give it a third try. I'm approaching 80k so I don't like having 7 relatively new plugs (changed at 60k) and one really old one.

 

[Terry]

Patman, another reason your nitration could be elevated on this engines analysis reports, tell me its not the Pontiac !

 

[Whimsey]

Patman,
Try squirting some liquid wrench or equivalent into the plug hole first. Then try to work the plug by loosening and then tightening the plug. Keep doing this back and forth movement and eventually you should free the stuck plug and loosen it. Trust me, it works.

Whimsey

 

[Terry]

Schaeffers Penetro 90 spray works well for this also.

 

[UncleS2]

Malibu, I remember the bad ole days of leaded gasoline, when most plugs needed replacement at 10 to 12 thousand miles! Since removing those originals in the Neon, I installed a set of NGK's("V-Power"copper core, most Neons don't like platinums, etc), ran those for about a year, then a set of Champions, still running those, will change in April or May, probably with another set of Champions, or maybe NGK's again. So, I'm now averaging ~26,000 miles on plugs.

As far as extending the life of the ignition system, I don't doubt it, but at 132,000 miles mine seems to be doing fine. When I removed those factory plugs, I also replaced the wires with a set of red Magnecors.

And, if need be, I have a spare coil pack in the carport closet.

 

[sprintman]

Patman This from NGK web site "Iridium superior to Platinum with higher melting point and higher resilience to oxidation offers a dramatic increase in durability and service life" Unique two stepped center electrode gives a secondary microdischarge burns off carbon deposits as they form. They have basically obsoleted Platinum plugs. Theres a good picture of the far better flame pattern too. fitted to both my vehicles and the change is immediately noticeable. Cost A$15 each here, must be cheaper in Canada?

 

[Patman]

Sprintman, they are about $17 a pair I believe, the last time I checked.

Terry, yes it's the Pontiac.

Problem is, it's hard to even reach that plug (if you've looked at an LT1 you'll know what I mean, it's plug #2) so we can't even easily get in there to spray anything at it.

I will bug my friend to give it yet another try this springtime though. Sooner or later it has to come out.

 

[Soma07]

Patman,

You did pull the alternator to get to #2 right? Otherwise I dont see how its possible... Removing that stupid lower alternator bracket off the exhaust manifold stud might help too.

Also instead of using a ratchet put the socket on the plug by hand and then use an open end wrench on the stocket.

 

[Patman]

Yep, my friend removed the alternator for sure. I wish I had headers on this car, my friend has Macs on his (I believe they are Macs) and he can do his own plugs in 45min! Mine took 8 hours with the wire change too.