Spark plug replacement - tools needed

Was this your "Service Adviser"?



:focus:

Thanks for the suggestions on the socket and extension. When I swapped out my plugs a month ago I didn't have the right size extension and my socket wouldn't hold the plugs despite being magnetized so I had to use needle nose pliers to insert the plugs into the hole. Grr

 

My spark plug socket has a rubber insert to hold the spark plug. Nevertheless, I use a length of rubber hose as my "tool" to start the spark plug into the hole. The idea is to use a hose with an inner diameter slightly smaller than the spark plug tail, so the hose will hold on to the tail.

The rubber hose will transmit sufficient torque to get the spark plug started. The idea is that if the spark plug starts to be cross-threaded, the hose will come free and you will avoid damage to the cylinder head.

 

I read about your garden hose idea and I started eying the girlfriend's garden hose once I realized my socket wouldn't work. I thought it better to use the pliers than to risk her wrath if she found a section of hose missing.

 

I was planning to purchase torque wrench and all and replace the spark plugs myself. This was because I was under impression that it would cost about 200 US$ or so
But when I went to dealer for a regular oil change and asked for a quote for spark plugs, my service advisor quoted something like 95 $ installed. I thought this was a very reasonable price and had the service performed then and there with a total wait of about 1.5 hour.

 

Be careful the little rubber insert doesn't come off on the spark plug when you put the new one in. This happened once to me and my brother when we were changing the spark plugs on my S10 a few years ago. We kept wondering why the wire wasn't going back on the plug properly. After about 20 mins of repeating the same thing over and over, I decided we should remove the spark plug and look at it. Needless to say, we found out the rubber piece was staying attached to the plug and that was our problem all along. Considering it had happened while removing spark plugs initially, you would have thought it wouldn't take us long to think of that....:doh:

 

That be a good one.

 

It definitely would not pay to upset your SO and I would not encourage you to take any action that might do so, in order to preserve domestic tranquility.

However, I'm not talking about a garden hose, which has a pretty large inner diameter. I'm thinking of a one-foot length of black 1/4" inner diameter rubber hose, like an automotive vacuum line. The hose will expand to grab the first 1/4" or so of the porcelain tail of the spark plug, and is sturdy enough to allow you to hand-torque the first few threads of the spark plug into the threaded hole in the cylinder head. It works amazingly well.

 

I used one those telescoping attenea type magnets you see at the checkout stands at hardware stores. It telescopes down to the length of pen or out to about 2' and even has a clip on it like a pen to hold in in your pocket if you want. Once my plug was loose I just stuck the magnet end down in hole and the plug stuck right to it and I pulled it out. They only cost a few $$ and yet it comes in handy in LOTS of situations.

 

Yes. I also have a telescoping magnetic wand and that has been very helpful in many jobs.

A recent Prius example: while replacing the 12V battery, the self-tapping screw that attaches the traction battery vent duct to the fender opening above the 12V battery slipped from my grasp and fell into the fender. The wand quickly retrieved that screw.

 

Adding my 2 cents..... I just changed mine after 145K.
The old plugs really didn't look worn... however I think it runs smoother when idleing although I had no real complaints before.

I apologize for the blurry picture... holding the wrench with my right hand and taking the picture with my left hand on my phone doesn't work so hot.



Take a 3/8 wrench and a sparkplug wrench.. while some use magnetic, mine had the rubber insert that held the plug quite excellent.

Remove the fusebox from the firewall.. 2 simple screws and it swings out of the way.

Take the small screw off the spark plug cap over the plug... once thats off the whole assembly lifts right out..... I did have to purchase a 6 inch extension as my 10" wouldn't work as it was too long... I think 8" would be too long also.

The first 3 are pretty easy... I took one out and replaced with new before moving to the next so as to avoid any mixups.

All 4 of my plugs were a nice toasty brown... not sure the difference between mine and the white ones in the previous pictures on this thread.... I use 87 octane and drive pretty aggressive "so does my wife" and thats what I got.



I did put anti-seize compound on the threads before replacing... very good idea since its so long between changes.

The last one to the extreme right was a little harder but not bad.
I had to remove the electrical connection because there was not enough slack to lift the whole thing out.
Take a look at the others to see how they lock because the view is a little crummy for the last one.
I pushed on the release with a small screwdriver with my right hand and wiggled it with my left....

I recommend when replacing to "not" bolt down before hooking the electrical connection so you have a better flexibility on getting the new connection back on so you can manipulate the angle as needed.

I didn't torque.. just a good respectable snug tightening with the wrench but didn't go crazy.

FYI..... I priced what it would cost for the dealer to do it...
First they told my 298.00 parts and labor.. when they heard me choke on the phone, they then said that was a mistake and it would only be 103.00.
I asked them now much if I already had the iridium plugs?....
they said 56.00 for labor only.

This was easy enough, it was worth doing it myself for 56.00.... especially since it honestly took me maybe 30 minutes setup to teardown.... and 7.00 bucks for the 6" extension I didn't have. I love the satisfaction of knowing I know how to do it myself too...
Was really a piece of cake..... no, I'm not a mechanic.

 

Thanks for the heads up on the Advanced Auto Part Magentic Socket, well worth the price. Made my life real easy.

 

Don't forget that 100,000 miles in a Prius may represent the actual road mileage, but the effective ICE "mileage" is considerably less than that, depending on your driving technique. On average I would guess that the ICE effective operational mileage is around 60 - 65,000 miles at 100K car mileage.

 

Tomiha,
Thanks a bunch! After removing the first 3 spark plugs, I ran into the fourth plug and was getting frustrated. I could not lift the coil. No room, No slack on wire.

I thought I had 2 options...
1) Remove surrounding components.
2) Remove wire clipped to coil.
Well undoing a clip sounds easy enough but I could barely see the clip and if I had the hands of a 5 year old boy I would still have difficulties sticking both hands around the clip.
I already had the relay box and air filter removed (this step takes literally seconds - no biggie). As I tried removing additional surrounding components, I was like how in the heck do I remove this, that the other. It was not common sense stuff and involved additional wiring, hoses, and housing.
I was getting upset.... I went to google and searched around for a bit. Googling terms like "Can't remove last spark plug on prius" and similar terminology. I found nothing helpful until I ran across your post. And you explained how to remove the most difficult plug. AWESOME and Thanks!
I used two regular sized flat screwdrivers and was able to remove the spark plug wire clip in no time.

Here are some other notes about my experience changing spark plugs on a 2005 Prius:
I had 108,999 miles on car when replacing plugs.

This is my tool recommendation list:
Compressed air
2 flat head screwdrivers - for removing clip on last spark plug.
10mm socket
A spark plug socket
Duct tape - firmly tape spark plug socket to wrench.
3/8 inch drive socket wrench - for removing plugs.
A 1/4 inch socket wrench may be better for removing relay box 10mm screws.
Anti seize compound - put on threads of new spark plugs. I was too lazy to buy so I just used WD-40 (carefully so as not to drip around plug)

I recommend using compressed air or an air compressor to blow away all loose dust/debris near top of engine prior to starting the job. You don't want anything falling into the engine.

You must remove relay box (attached by two 10mm bolts, and it's very helpful to remove the air filter housing - just the lid will do). This step should be very easy.
Don't use anything smaller than a 3/8 socket wrench when removing plugs. For the simple fact that you can get a little more momentum (torque) when loosening plugs in a tight area.

I had to use only a little ummph when loosening all the plugs, even though the car had almost 109,000 miles on the original plugs. By no means would I say spark plug loosening was difficult. I was happy about this fact. Relax, chances are you will not have to strain a neck muscle to remove the old plugs after 100,000 miles.

I strongly recommend firmly placing duct tape around spark plug socket to secure it to the socket wrench. The very first plug I tried to remove had the socket come off and I lost a few minutes trying to retrieve it with the loosened plug still attached. Plugs 2,3,4 came out easily because I had the socket taped to the wrench. 1 layer of tape works great, too many layers and you will not fit wrench into engine!

Always place the extension bar with socket attached into the engine first THEN connect the socket wrench. Without doing this you are in for a much rougher time. Also reverse the process once plug is completely loosened. Take remove wrench from extension bar, then SLOWLY pull out the extension bar so as to not drop the plug while lifting, you will have to angle the bar towards front end of vehicle during lifting process to remove. Somewhat tricky but not brain science.

I used a spark plug socket, and a 5 inch extension bar on my 3/8 inch socket wrench. A spark plug socket is simply a normal socket with a built in rubber housing to properly grasp the plug and reduce risk of stripping.

For gosh sakes do not use a 6 inch extension! I tried and think it's impossible to work with due to space limitation. 5 inch is perfection, I bought mine for $5 at Autozone.
The second spark plug (second from left hand side while facing engine) I removed broke while loosening (likely due to age). Luckily it was a clean break. I was able to remove both pieces by placing duct tape on the inside of the spark plug socket and slowly lifting out of the engine.

Fourth plug located closest to the driver side of vehicle is by far the most difficult. Keep the following in mind:
1) REMOVE THE WIRE CLIP!!!!
To do so, I use two flathead screwdrivers, I lifted the clip slightly upward from inside (this is risky too much force and you can break the clip) I did it this way because I was getting nowhere trying to push downward for a release (the correct way). While slightly prying upward from inside the clip release mechanism I simultaneously was pushing the edge of clip outward - Worked beautifully.
2) The fourth coil was the most difficult to remove EVEN AFTER removing the wire. Limited space was the problem and it was a little stuck due to age. Have some patience, you can do it. Push the loose wire clip away from the coil area as much as possible.
3) Once coil is removed, removing the spark plug was the same as the first three, not too difficult. Always slowly pull out the extension bar after taking off the wrench and you should be fine (remember what I said - duct tape the socket to the extension bar - this will likely save your buttocks)
4) After installing the 4th and last plug, don't tighten the coil yet, leave it loose. You have one more tricky part to go through (dang fu#%!!g 4th plug). FIRST rearrange the wire - it was wrapped under the cluster of 4 coil wires, simply move this wire on top of the cluster by gently pulling the connector from underneath the grouping. This should be easy and will give you additional slack to reconnect the clip to coil. You will not need to remove any wire housing or tape etc. Just move it from underneath to on top. Finally connect it to the coil and tighten the coil 10mm bolt. Reconnect your relay box and air filter housing, YOU ARE DONE! Congrats!

 

NOTE: If you use a 6" extension, you will have to wriggle is around to get the last two plugs out... it can be done, but a 5" would work better.

NO KIDDING! I used a 6" extension and added a good 15 minutes to the job. I suggest replacing the plug on the far right first, observing recommendations on the cable clip. Once you are done with #4, the rest will seem like a piece of cake. 110k miles and they look good, but I was having some chatter and idling problems that are now gone.

Thanks for the post!

 

Note for those replacing their spark plugs with NGK plugs:

DO NOT USE ANTI-SEIZE when installing NEW plugs. All NGK are made with a special shell plating that eliminates the need for anti-seize. If you do, you risk over-torqueing the plugs.

http://www.ngksparkplugs.com/pdf/TB-0630111antisieze.pdf
http://www.ngksparkplugs.com/pdf/DYK_5Points.pdf

 

Quick Question guys, esp. Patrick. Is a torque wrench needed to do the job? There is another spark plug thread out in PC land that mentions torque settings but I didn't see anything here.

 

Yes, it is important to observe the correct torque since you are dealing with the aluminum head and valve cover and it is easy to strip the threads.

iridium spark plug: 13 ft.-lb
igniter bolt: 82 in.-lb
relay block bolt: 74 in.-lb

 

Thanks, I'm having a real tough time finding a torque wrench that can go below 10 ft/in. Any suggestions?? I've never been a DIY until we got the Prius so I really have no tools

 

"10ft/in" is kind of meaningless. Torque is a measure of force x distance; the most common wrenches are calibrated in ft-lbs or inch-lbs. If you had a regular box wrench with a 1-foot handle and a fisherman's spring scale, you could attach the scale to the end of the handle, and if, while pulling on the scale, it read 10 pounds, you would be exerting 10 foot-pounds of torque on whatever the wrench was trying to turn. A torque wrench just combines the scale with the wrench and allows you to read the torque directly, by various means.

Amazon has a whole bunch of torque wrenches available. You can look through their catalog , and you'll see there are 3 basic types: a beam wrench, where the handle actually bends, moving a scale under a fixed pointer; a click-release wrench, where you set the desired torque and the handle clicks and releases the pressure when the desired torque is reached; and what I'll lump into "Other" -- an assortment of gauges, digital, and usually expensive, high-tech stuff.

The drive end of the wrench will be a standard 1/4", 3/8", or 1/2" square drive. The smaller the drive, the lower the torque. Usually you can find a 3/8" drive wrench that will cover the range you most often use.

In critical applications, you can't just buy a torque wrench and wrench away. The wrench must be periodically calibrated to known standards, adding more cost to an already expensive tool. For automotive applications, a decent click-wrench can be had for under $100, but you really need more than one, since the wrenches only work over a defined range. For the Prius spark plugs, you'll need one that works accurately at 13 ft-lb (or 156 inch-lb).

Accuracy tends to be best at the middle of the tool's stated range, so a decent choice might be the "Snap-on Industrial Brand CDI Torque 2502MRPH 3/8-Inch Drive Adjustable Micrometer Torque Wrench, Torque Range 30 to 250-Inch-Pounds" for about $125. There are cheaper and more expensive ones out there. Snap-On used to be an excellent tool, and is still the choice of many pros, but other brands are catching on.

 

Thanks, I made a mistake in my original post. I meant too type 10ft/lb. Anyway here is the winner: Amazon.com: Neiko Professional Grade 3/8-Inch Drive 40-250 inch-lb Automatic Torque Wrench: Home Improvement