spark plug replacement

The Checker computer will probably suggest any spark plug that will physically fit into the hole and has the correct heat range. The correct NGK plug is IFR5A11, while IFR5T11 is an acceptable substitute.
http://www.ngkntk.co.uk/working/FileLib/1010 IFR5T11 Spark Plug.pdf

Looks like BKR5EIX11 does not have a platinum disc on the ground electrode while the correct OEM plug does. So you can expect BKR5EIX11 to have a shorter life.
NGK Spark Plugs USA

I suggest that you use the correct plug, obtain a wire spark plug gap gauge of 1 mm or 0.039", and adjust the plug gaps accordingly before installation.

The OEM Denso plug is good for 120K miles on 2G. The IK16 plug is good for 30K miles according to Denso's website.
Frequently Asked Questions: DENSO Iridium

Q. How long will Iridium Last?
A. Iridium use represents the most significant technological advance in automotive spark plug manufacturing, since platinum was introduced in the early eighties. As vehicle manufacturers produce increasingly complex and efficient automobiles, there is a greater need for long-life plugs that can tolerate leaner fuel mixtures and improved combustion processes. DENSO has responded to this need by developing its Iridium alloy, originally for OE applications. For example, many newer Lexus’ and Toyota models carry an ultra long-life Iridium plug variation (.7mm with platinum tipped ground) that is capable of up to 120,000 miles of service. DENSO Iridium Power plugs, with their .4mm center electrode, have been developed for performance applications. Because gradual wear will “round-off†firing points over time, the concentrated firing power and voltage requirement benefits will be reduced. For this reason, DENSO advises replacement after 30,000 miles.

 

I've tried the penetrating oil trick on older vehicles. It does not help remove spark plugs.

What usually happens, the threads are seized/galled. Heli-coil to the rescue

 

At 113k miles, I just replaced my spark plugs. NKGs were in it and they were replaced with Denso (came in the Toyota box).

NKG at 113k miles look amazingly well! The one on the right looks like almost new. I replaced them anyway since I was installing a new PCV, Tanabe Sustec Pro and their Tower bar.

 

On the right plug, is that a bit of rust on the threads?

 

No, I think it is the background color. You can see it if you zoom in. Let me know if you want me to post a higher resolution pic.

 

No, thats ok

 

I recently replaced the iridium spark plugs on my 2004 at 98K miles, using the correct Denso plugs. I had previously put antiseize lube on the threads at ~30K miles. The old plugs came out without difficulty but the threads seemed to cause substantial rotational drag as I was removing the old plugs.

I installed the new plugs without using more antiseize lube. The new plugs went in easily so I assume the problem was caused by dirty spark plug threads, and not the cylinder head threads.

I noticed an error in the Toyota repair manual that I wanted to call to the attention of the group. If you refer to the ignition section of the manual, you will see that the spec is 1 to 1.1 mm for a new plug. However if you look in the diagnostics section of the manual and read about DTC P030x, you will see a spec of 0.7 to 0.8 mm for a new plug. This inconsistency exists in the 2005 and 2006 docs, it probably persists throughout the 2G model year range.

I am assuming that 1 to 1.1 mm is correct, and set my new plugs to 1 mm. The factory-set gap is wider than that.

 

Is a spark plug socket different from a regular socket? Thanks!

 

Yes. A spark plug socket is deep, and has a rubber liner within which will grab the spark plug porcelain tail so that the plug won't fall out of the socket. The liner cushions the porcelain spark plug tail and ensures that the socket is placed squarely, thus reducing the chance of snapping off the tail when installing or removing the spark plug.

 

Thanks! Also Is the socket for spark plugs English units (5/8) not metric?

 

I use a 5/8" spark plug socket because I first started buying tools 35 years ago, working on domestic vehicles that I owned at that time, and the socket fits nicely. You can buy the equivalent 16 mm metric size if you like, but you may find that SAE sockets cost less than the equivalent metric sockets.

 

Is it really necessary to disconnect the 12V battery before removing the plugs? What potential harm does it prevent? Thanks!

 

No, it is not necessary as long as you ensure the car is IG-OFF before you start.

I suppose the potential harm that is prevented is if you left the car READY before you started to work on it. Disconnecting the 12V battery guarantees that the car is IG-OFF.

 

Any specific recommendations for the brand/type/kind of anti-seize lubricant is recommended for the iridium spark plug threads?

Does Toyota service use anti-seize lubricant?
Thanks
Dave

 

I'm sure the Toyota techs just jam 'em in dry. You can get the
high-temp anti-seize at any auto parts place, it looks like
silvery-grey grease, and one smallish bottle will probably
last a lifetime unless you're doing a lot of heavy-iron repair.
.
_H*

 

I was planning to replace my own sparkplugs with all nice info at PC. But my dealer had a price of 96$ installed. So I got it done by the dealer.

I guess I would have ended up spending atleast 75$ myself considering I would have had to purchase Torque wrench.

Also I do not think replacing spark plugs would have given a that much of satisfaction that a major DIY job would provide. So $$$ saved had to be the driving factor.

 

If it's of interest, there is a nice click-type torque wrench at Harbor Freight that will only set you back about $20 regular price and ~$12 if you can find one of the coupons they've been distributing lately. You can find the NGK sparkplugs at Advance Auto for about $7 each, so the whole job can be done for less than $50 without too much time or trouble.

 

Thanks, It was nice to read a writeup before jumping into this small project. I just replaced the plugs in my 2004 prius and did it in an hour and half taking my time. And thats with disconnecting the battery and cleaning the ignitors and using boot lube and antisieze. I did notice rust on #4 so I'll keep an eye on that area in the future during the winter and heavy rains. Just to add, maybe I missed it but #4 igniter was made a bit easier by removing the three bolts that hold the wiring guide around the valve cover and using a small screwdriver to push down on the tab while pushing the connection apart.
I think they were the original plugs with 123,000 miles. I bought it 2 wks ago and was a little concerned about some ticking noise from the engine and hoping it wasn't the valve clearance. Turns out it might have been the plugs arcing? She purrs like a kitten now.

 

Appreciated all the input on PC - even simple jobs can be made much easier knowing what your getting into before you start. But before I start I need parts.

We bought our 2005 w/ 85k on it, now it has 124K and I don't know what the repair history was. I'm getting ready to replace the coolant valve (P1121 code), inverter water pump (preemptively), invert coolant, engine coolant, PSD fluid and decided while I'm at it to do the sparkplugs. I think I've found everything I need online from ToyotaParts/AutoPartsPeople and Champion/Trademotion except the sparkplugs.

I was wondering if any out there have found a good online source for the OEM plugs? Since I need to buy several service items I hoped to buy them all in 1 or 2 places online to save $$$ on parts and shipping costs, strangely most all the Toyota parts places I've tried online come up with no part found when I try searching for the iridium sparkplugs.

One site came up with "part# 0308-19100P" along with "#919-01240" and a "mfgr. Note SK16R11" but showed "Not available". All other toyota part sites show no part found - I've tried the (apparently incorrect) part numbers listed above and 2 additional part numbers I found on PC (90919-0128 & 90919-0217) as well as searching for SK16R11 or even sparkplugs...all searches come up no part found! Maybe they are made from unobtainium? What's the deal?

I did find plenty of hits doing a google search but then I would need to buy from yet another source w/ additional minimum shipping costs. I just can't believe all the Toyota part places that sell every imaginable Prius part can't sell sparkplugs. Am I using the wrong numbers or what?

 

Toyota part numbers typically have 10 digits. Here is the correct part number of the iridium spark plugs: 90080-91184. I paid $10.67 each last June at Champion Toyota, Houston.

An alternative is to buy those plugs from a GM dealer. $4.98 at this source, see my post #4 and enter the GM part number 94859448 after you go to the GM dealer website: http://priuschat.com/forums/gen-ii-...shooting/83507-cheaper-gen-ii-sparkplugs.html