Can you/did you replace your own spark plugs?

there is a walkthough on here somewhere, I have it bookmarked for when i reach 100K, do an advance search under only the gen II maintenance forum. it is very difficult and time consuming as it involves removing a lot of stuff including the wiper arms and motors, a rain collection tray and other things. it is also recommended that you replace your PCV valve when this is done as it only takes a couple extra minutes, is a dirt cheap part and gets clogged easily.

now if only dealership technicians could anonymously post their "after hours" rates on here without fear of termination . . .

 

It actually is not necessary to remove the wipers, cowl etc. All that is required is to remove the relay box over the engine, for access to the spark igniters and spark plugs.

The Prius spark plug change is simple and easy compared to many vehicles (for example, V8-equipped SUVs where you need to raise the front on jackstands and remove the front tires for access to the spark plugs via the wheel wells.)

 

Pat I remember you lamenting your Ford spark plug change. I had a 1999 Ranger that was the worst too. Through the fender wells and the last one pass side really pissed me off. Just stupid.

 

Just bring your Prius up to Sacto and I will only charge you $10.00

 

UMMM - Where did this come from ?? No - it is NOT that difficult - There's only 4 plugs/igniters to deal with. I would suggest that you DIY.

("Borrowed" from another recent post)

Tools needed
1. Torque wrench 3/8" drive
2. Medium lenght 3/8" extension or 2 small hooked together
3. 5/8" sparkplug socket
4. 10mm socket
5. 3/8" rachet
6. spark plug gap tool

0) Check the gaps on all new plugs and ensure gap is set to .043" (if not, carefully adjust to the proper gap)
1) Open the hood
2) Remove the relay box in the center of the engine compt (above the spark plug coils (just below the windshield) and move aside.
3) Remove the 10mm bolt and unplug the first coil/sparkplug wire (a black cable on the top of the engine secured by a 10mm bolt (there are four of them)). I went from left to right
4) Using the spark plug socket, and 3/8" extension lower the socket into the hole and turn until it slips over the hex portion of the spark plug
5) place rachet on end of extension and turn counter cw to remove the spark plug. The spark plug will remain in the socket when completely unscrewed
6) Insert new sparkplug into socket and lower into the hole using 3/8" extension (rachet removed)
7) Hand tighten spark plug until it stops
8) Set torque wrench to 13 ft/lbs, attach to extension and tighten to that setting
9) Replace coil wire and tighten bolt
Repeat steps 3-9 for remaining plugs
10) Replace relay panel
11) Jump up and down and congratulate yourself for saving $200

 

Hi cnschult, I think you've got that confused with the procedure for changing the PCV valve, which does require removing a fair bit of stuff to get access on US model. (On overseas models without the thermos tank however, even the PCV valve is very easy to get to.)

 

I did set out to replace my plugs but found them to be in such good condition that I just cleaned them up and put them back in. I am confident they will last for another 50,000++++ miles. If you do the research, the plugs are irridium tipped. Irridium is one of the hardest, most corrosion resistant metals known. I would say the best plugs to get are the ones you already have. Just clean them up with a wire brush and some crocus cloth. They will be as good as new.

 

Here is a pic of one of my plugs after I cleaned it up. Looks almost brand new. No noticeable wear on the center or side electrode. I've never seen plugs in this good of shape after 100,000++++ miles. This is true for both my 01 and my 06.

 

I bought a new set of plugs at Amazon a couple of years ago for about $30, and finally got around to putting them in yesterday, at 96,053 miles. I had also seen the take-everything-apart instructions, and put the job off because it seemed so daunting. All that turns out to be BS -- tv4fish's summary above is spot on. I substituted a standard 5/8" deep socket, a magnet, and a 6" piece of 1/4" ID vinyl tubing for the special spark plug socket, and feel it was a much more manageable job in the confined space than it would have been using the special socket.

My plugs were pretty badly eroded, at the upper limit of gap tolerance, with a lot of buildup on them, so I wouldn't have considered cleaning and reusing them, even as emergency spares. I have a professional spark plug cleaner, and even the manufacturer recommends NOT cleaning platinum or iridium plugs. At only $7 or $8 for the new NGK IFR5T11 plugs, it's cheap insurance for keeping the ICE running smoothly, and the igniter assemblies cool.

 

You still living in Sacto, Andy? I have a 2005 that needs new plugs and the $200 or so labor charge is not in the budget. If you're willing to give me a hand for some $, let me know.
Thanks!

 

It's 2017 now, 5 years after the last post in this thread. I live on the outskirts of south Seattle. The motor sounded a little rough, and Toyota of Burien offered a "tune-up" for only $330. I declined. Found this post and followed tv4fish's instructions above for my 2007 Prius, which is at 106K miles.

Moving left to right and completing one at a time, the fourth spark plug (the one closest to the driver side) gave me some trouble getting out. This is because there's a black piece of black plastic just to the right of it that restricts movement. Had to clip off a wire tie, tug upwards semi-gently/consistently, and disconnect the igniter's cable clip (I didn't have to do this for any of the other 3 spark plugs) before I had enough room to pull off the igniter. So don't give up if you encounter this problem when you're changing yours! It can be done. Be persistent.

I didn't need a magnet to pull the spark plugs out. Just take the 3/8" drive ratchet off, pull up just a little and then angle the extender to apply pressure on the wall of the channel with the bottom of the spark plug. Then gently pull out, keeping the bottom of the spark plug in contact with the wall to keep it from dropping out of the bottom of the socket.

Tested after the process and the car runs sweetly like the little four banger it is.

I used:
- a 5/8" socket,
- 6" medium length extender
- 3/8" drive ratchet
- 10mm socket
- 1/4" drive ratchet for the 10mm socket
- 4" extender for the 1/4" drive ratchet
- spark plug gap checker

I already had the 10mm socket, 1/4" ratchet, and 4" extender. I bought the rest with these two links from Amazon (I have Prime, so 2-day shipping was free), and 1 from ebay.

Performance Tool W1131C Ignition Tune-Up Kit, 4-Piece
$12.99

Lisle 67870 Spark Plug Gauge Gap
$2.99

(The prices may vary on Amazon. Use the Camelizer to get a browser add-on that tells you if the price is currently the cheapest.)

4 IFR5T11 Spark plugs from eBay
$25.99 and free shipping

So $42 all told, and I got some new tools out of it.

 

Man I was dreading removing the wiper assembly. Looking at it was gonna attempt what's suggested here. Thanks All!

And didn't know about the PCV.

 

The wiper motor removal is for 3rd gen. so much fun...