Changing the spark plugs (11 Viewers)

[mark71]

Decided to do my first "How To" posting since this wasn't as straight forward as I would have hoped. This procedure, due to the much tighter clearances under the hood, is a little trickier than the Tundra. Here is how I did it, starting with the passenger's side.

First, loosen the clamp on the air box.

Then remove the wire harness from the air box.

Then remove the three bolts holding the air box on and slip the air box out (finger is pointing to the third one).

Now you have access to all the plugs on the passenger side except the firewall plug (sorry, poor lighting).

To get to the firewall plug, remove the three bolts holding the black electrical box (finger pointing to the third bolt).

 

[mark71]

Disconnect the wiring harnesses from the firewall. To do this, flip the gray lever all the way up and the plug will disengage.

Release the wiring harness thingamajig that hold the wire bundle. This will help move the bundle out of the way.

Now I loosened the coolant tubes overlying the plug. There were two in this area.

 

[mark71]

Now I removed two more bolts on another set of coolant tubes to free things up all the way. Sorry I don't have a pointer, but I tried to place the relevant bolts in the center of the picture.

Now, the assembly can easily be pushed up out of the way to remove the bolt securing the coil.

And with a little downward pressure on the coolant tube assembly, the coil is rotated 90 degrees and slides out. This, of course, requires you to first disconnect the harness to it by squeezing and pulling off. Needle nose pliers are very useful for this.

The plugs are quite deep in there, so an assortment of extensions, swivels, and beer makes the project go much easier. Remember, don't over torque the plugs when you put the new ones in: the head is aluminum and not forgiving. I'm a big believer in anti-seize and used it on the threads. After making contact, I turned the plugs 1/2 turn further (manufacturer's suggestion) rather than using a torque wrench .

I hope this helps and good luck.

 

[MScruiser]

This is great!

What sized plug socket did you use?
What plugs did you go with?
What were the part numbers?

 

[Romer]

Thanks for the write-up. I added it to the FAQ. Why do you have to take the harness off from the firewall?

Do you have any pics of changing the plugs to add?

 

[mark71]

This is great!

What sized plug socket did you use?
What plugs did you go with?
What were the part numbers?

5/8" spark plug socket (has little rubber dohicky to hold the plug in the socket) and assorted other tools.

 

[mark71]

Thanks for the write-up. I added it to the FAQ. Why do you have to take the harness off from the firewall?

Do you have any pics of changing the plugs to add?

If I remember right, I needed to do that to get more movement from the electrical box (relays?).

I didn't take pics of changing the plugs themselves. Once the coil was removed, it is pretty easy but each plug did require it's own combination of extension lengths and swivels to clear the various items in the area. Trial and error.

 

[Romer]

What year is your cruiser?

How many miles does it have (Between plug changes)?

What did the old plugs look like, did they look like they needed changing?

 

[mark71]

What year is your cruiser?

How many miles does it have (Between plug changes)?

What did the old plugs look like, did they look like they needed changing?

My 2008 has 130,000 and this was its first plug change. It was a little early, but I wanted to see what they looked like (normal) and didn't want to go through all this again in 20,000. Gap was normal also (0.044).

I'm glad I did, because I found an oil leak down in the valley where one of the plugs sit. I will report back once I know more, but I may have a valve gasket kit in my future.

 

[DSallean]

Thanks for the write-up mark71. I used this as a reference for changing my plugs last weekend. Mostly to get to the passenger/firewall plug which is a little tricky to figure out and much easier with these posts and pictures. It's the first plug change at 129,000 miles and the original plugs looked pretty good.

It's a fairly straightforward job but as mentioned above you will use an assortment of extensions and a swivel to change the plugs. Be careful not to drop the rubber gasket that seals the coil to the valve cover. I dropped one then spent a half our trying to retrieve it!

 

[1HaytchZed]

So is there a reason, NOT to use the Denso SK20HR11, being OEM?

 

[Mogwai]

So is there a reason, NOT to use the Denso SK20HR11, being OEM?

FYI this was not the same part # for the OEM Denso Iridium I just picked up from Toyota Escondido, the ones I got were 90919-01191, these seem to cross reference correctly on the internet (for a 2013) whereas I got a "does not fit" when querying your part number to my truck.

 

[1HaytchZed]

FYI this was not the same part # for the OEM Denso Iridium I just picked up from Toyota Escondido, the ones I got were 90919-01191, these seem to cross reference correctly on the internet (for a 2013) whereas I got a "does not fit" when querying your part number to my truck.

Searching on Amazon, Ebay etc comes up with the Denso PN SK20HR11, which are the Toyota PN 90919-01191 plugs. For all 3UR applications.

 

[Mogwai]

Searching on Amazon, Ebay etc comes up with the Denso PN SK20HR11, which are the Toyota PN 90919-01191 plugs. For all 3UR applications.

Ok I stand corrected, that part number is also in the 2008 manual, my first look on Amazon showed it wasn't compatible with my vehicle, didn't look much further. Thanks for clarifying.

 

[kyoso23]

Great write-up. Moving the electrical box and removing the plug from the firewall made this a piece of cake.

 

[Mogwai]

I finally got around to changing my plugs, at 109,225 miles. Plugs all looked pretty good, slight rust on a few of them. I think I put this off for fear of finding oil in there

I didn't remove the electrical cable or back fuse box, just the 2 bolts that hold down the coolants hose bracket closest to the firewall. I did however disconnect 3 of the coolant hoses to get better maneuverability, spilled about a cup of coolant all over the place, which is probably why FSM says to remove the bottom plastic cover under the truck (plastic skid plate thing - don't know what it's called). Otherwise I'm not sure why that's part of the process.

Pretty straight forward, definitely needed to use two 3" extensions for the driver side, put one on the spark plug socket, lower it in a bit, and then add the other. Hand spin and then I was able to use a standard size 3/8" torque wrench (15lb*ft) on each w/out issue. Did an oil change too. Fired her up, and didn't really feel any difference. '

Edit(s):
*I did unclip a couple of the smaller elec wires on driver side, to move them out of the way.
*attached the 3 FSM pages

 

[Weedhopper]

THIS stuff makes removing a stubborn plug easy. I was terrorized when the (of course) last plug got stuck as I was removing it. Dry threads locked up and the plug would not move at all.

A good spray of this stuff cools the plug, probably shrinking it a bit, and it penetrates to lube the threads.

It literally saved me from having the truck towed to the shop for a repair.

 

[Gr8Pmkn]

Just wanted to say thank you! Just finished changing them on my 2014, was able to do in about an hour and a half. The instructions for unbolting the coolant lines and wiring loom made it very doable.

 

[sixsixnine]

Just knocked this out today as part of baselining my ‘new to me’ 2013.

I want to start by saying thanks for the detailed write up, and that I’m only slightly mechanically inclined. That being said, it still only took about an hour and a half from start to finish. It’s not a difficult job at all.

Driver’s side was unremarkable. They’re all completely exposed.

Passenger’s side was a little more time consuming, but once you unbolt the four coolant hose brackets mentioned in the photos, everything is pretty straightforward. I did the firewall plug first, so it was all smooth sailing after that.

Like the other posts have said, a variety of extensions will make your life much easier. I didn’t remove any of the wiring loom, either.

 

[fasteddie2015]

Dredging this up again. So if I'm removing the two wiring connectors (airbox and fuse box) I assume that I need to disconnect the battery first. Is that right? And if thats true, what's involved in rebooting the LC after I'm done? I've changed plugs on my Lexus GS400 and gen 1 Tundra, but this seems a little more involved, plus there's more electronics on the LC than both of the others combined.