06 Legacy plug questions

[ron2368]

I purchased a used legacy and my mechanic gave me a quote of $150 to replace the plugs. First off, at 30k do I need to do this, what kind of plugs are in this car? How long should they last?

If I do this, do I need special tools or is there a trick to doing it? It looks like a tight job at the least, there must be an easy way to do this( at least I hope there is). thank you

 

Another ?. The brake fluid looks ok, can I just replace the fluid in the resorvoir or does it need a full drain?

[nipper]

I usually like to start all new with a used car, but you have such low mileage i'm going to say skip it. If you have no miss, no CEL, decent gas mileage, and pass emissions your good.

 

Plugs should be replaced at 100,000K no matter what

 

nipper

[OB99W]

Subaru-recommended maintenance schedules can be found in the owner's manual, or at http://www.subaru.com/owners/schedules/index.jsp?from=topNav . Click on model year, then on the appropriate link at the bottom of the page.

 

As to plug change interval for 2006, Subaru apparently specifies 60k for the Turbo or 3.0L, but only 30k for the N/A 4; that may or may not be conservative.

[ron2368]

What is the oem plug for this car? Since they call for a 30k change is it a platinum or a standard plug. I was going to pull one but I figure I may as well have its replacement ready to go in. Ngk shows an iridium on their site, they dont even show platinum as oem, what is best to buy as a replacement?

[WAWalker]

OE NGK plugs are FR5AP-11 Platinum, for the 4 cylinder engine.

 

Subaru does recommened replacing at 30k miles. Do they need to be? Probably not till 60k.

 

As nipper said, if it runs good, fuel milage is good, and passes emissions..............they don't have to be replaced.

[OB99W]

Take a look at http://www.ngk.com/results_app.asp?AAIA=1432742

(This is for the H4.)

 

If you get platinum, get the double (OEM type) -- the wasted spark ignition arrangement has opposite polarity on two of the four plugs, making single platinum a poor choice. I agree that if things are running well, you can hold off on changing plugs.

[forester2002s]

I put single-platinum plugs in my 2002-Forester about 40,000-km ago, before I knew any better.

 

Can I switch them over to 'the other side' and run them there for a while? To even out the wear... a bit like rotating tires?

 

Any thoughts?

[OB99W]

I put single-platinum plugs in my 2002-Forester about 40,000-km ago, before I knew any better.

 

Can I switch them over to 'the other side' and run them there for a while? To even out the wear... a bit like rotating tires?

Are you noticing any problems (at what would be equal to about 25,000 miles)? I suppose you could swap the plugs around, but I'm not sure that would be "fun". If it were me, I'd just run them until they gave signs of needing replacement, or you had some reasonable mileage ("kilometerage"? ) on them, and then put in doubles.

 

If you do decide to swap them, the wasted spark "pairs" are the ones that share a coil in the coil pack (1&2, 3&4), so exchanging #1 with #2, and #3 with #4, would accomplish what you suggested.

[dhewitt]

We did the same thing with our '03 Outback before we knew any better - put in regular platinum from NAPA (don't recall brand). Lost gas mileage and replaced with NGK. Better.

[davebugs]

OE NGK plugs are FR5AP-11 Platinum, for the 4 cylinder engine.

 

 

 

An update to this.

 

My ex girl friends car is due for the timing belt so it'll get new plugs, idlers, accessory belts, etc. The water Pumps are double the cost of the SOHC's so it'll stay on this one - she's tight on cash, the tensioner will be re-used as well.

 

Anyways based on my notes I installed NGK FR5AP-11's last time. The NGK site calls for FR5AP-10's and the website says the factory gap is .39 and my notes indicate .44.

 

Haven't checked them yet but typically NGK's are good to go out of the box. A little apprehensive about gaping an exotic plug.

 

But the real reason I'm powsting here is that my local parts place has an old NGK book. It states that the -11 means wider electrode (or tip - I forget). Which may be sort of the answer since they aren't grooved like the cheapies I use on the 95-99's.

 

So while I haven't checked the gap, or decided whether to gap them if they are .39 and should be .44 atleast the -11 is somewhat explained if someone searches for this in the future.

 

One further note. What are listed as "double platinums" on the NGK site actually say "laser platinum" on the box. They are what came out from the factory last time and what I installed at 51k now the car is pushing 100k. The original plugs looked good to the naked eye but had started to get tight due to galling(sp?). I anti-seized and dielectric greased them so we'll see how they are this time. I'm thinking that if the factory would have used anti-seize they may have lasted 100k. I'm thinking the recommended replacement frequency had more to do with the ability to remove the plugs than wear - YMMV.

 

For science if anyone wants one to put under a microscope or anything PM me because I'll try and save the old ones for a while. It may be valuable research for other members to help them make replacement frequency decisions.

[OB99W]

To clarify the -10 or -11:

10 mm = .39 inch

11 mm = .44 inch