Tried a search, sorry if I missed similar posts.

 

Looking to change the plugs in an 06 Forester, 2.5 n/a.

 

Have the plugs and new plug wires.

 

How involved is this, what are common mistakes to avoid, potential problem areas etc? Any specific tools needed?

 

Thanks, Matt.

Tried a search, sorry if I missed similar posts.

 

Looking to change the plugs in an 06 Forester, 2.5 n/a.

 

Have the plugs and new plug wires.

 

How involved is this, what are common mistakes to avoid, potential problem areas etc? Any specific tools needed?

 

Thanks, Matt.

 

You'll need a universal joint for a 3/8 ratchet, and a couple of extensions. Plug gap is 0.042".

Take the wires off one at a time. I always add a small smear of antisieze compound to each plug thread; this makes them easier to extract next time and prevents carbon from creeping up the threads, which can abrade the threads in the aluminum cylinder head. Take your time, don't overtighten the new plugs.

You'll need a universal joint for a 3/8 ratchet, and a couple of extensions. Plug gap is 0.042".

Take the wires off one at a time. I always add a small smear of antisieze compound to each plug thread; this makes them easier to extract next time and prevents carbon from creeping up the threads, which can abrade the threads in the aluminum cylinder head. Take your time, don't overtighten the new plugs.

 

The above advise is very good. I also add dielectric grease to the inside of the plug wire boot. Makes it easier to remove in the future, and locks out moisture. Don't be surprised if old wires are a bear to remove, mine were. I had to rip them to pieces to remove, just would not release from the end of the spark plug.

Thanks for the replies. Is there a procedure to removing the plug wires? Do you need to turn the boot or anything like that?

Thanks for the replies. Is there a procedure to removing the plug wires? Do you need to turn the boot or anything like that?

 

I rotate the boot left to right several times, then pull and wiggle the boot around until it releases. However, I tried this on my 99 OBW with prolly 10 year old OEM wires. Those suckers were heat baked hard onto the ends of the plugs, and wouldn't come loose for anything. Finally, I yanked the boots off with channel locks. What came off was in torn pieces, but it was the only way to remove them. Hope you do better.

 

I am not familiar with the under hood of a Forester, but I am sure it is similar to a Legacy. If like the Legacy, you may need to remove the battery, windshield washer reservoir, and air intake unit, to gain access, and work room to get at the plugs.

 

Just be sure to hand tighten the new plugs upon installation, before using a drive to fully tighten down the plug. This avoids the possibility of cross threading the plug upon installation, but you prolly already know this.

Own a 2006 Forester, and I change my own plugs. To do this job you will need:

 

1. A torque wrench. Others will disagree, but you can screw up the spark plug threads by either too tight, or too loose.

 

2. 2- 3" extentions. Preferably the locking kind that can be bought at Sears. One 6" extention will not work.

 

3. A swivel may be helpful.

 

4. A spark plug socket with rubber retaining plug.

 

5. A piece of washer hose, or other tool, to gently start threading the spark plug without cross threading it.

 

You will have to remove the air filter enclosure to get room.

For a reasonably experienced amateur wrench changing the spark plugs is not too bad. I would NOT recommend this task for a beginner. Stripping the spark plugs holes is guaranteed to ruin your day. It's a fairly easy job, once you know how do to it. Given "stealership" labor rates, even a torque wrench pays for itself pretty quickly.

Edited May 1, 201213 yr by The Dude

Thanks for the good tips. I have done a lot of work on old Fords, and I've changed the pkugs in a Loyale before but wanted to be sure there wasn't anything too unusual about the Forester before I jumped in. I've never cross-threaded a plug myself but have been there when happened. Learned a couple of new words that day.

before you tackle this job, what plugs and wires did you get?

 

stick with NGK plugs and NGK/DEALER wires or you will do them again soon.

That's what I have. Will attempt this over the wknd- standby for an update.

You also might put a little tape over the extension end (another wards cramming into the socket until is joined firmly to the wrench) before starting. Several times I have the extension and socket remain deep in the engine as I pulled out the tool:(