Best spark plugs for 05 Prius

I really doubt that you can find a plug that will give you an increase in mileage compared to the stock plug. There is a lot of snake oil in spark plugs and oil. As long as the spark is sufficient to burn the air/fuel mixture in a smooth manner you are good to go. Extra electrodes in a low compression engine such as the Prius are not going to do much other than cost you more money. What you should do is remove your plugs and note how they are firing. Are they oil fouled or are they burning the fuel well. You should see an even medium tan to dark brown color. If they are black then they have been burning oil. 120,000 miles is a lot of mileage for a plug. Be careful when taking out the plugs to not allow dirt and other stuff to fall into the plug holes. Then hand turn the plugs when you first put them in to insure that you do not strip them. They need to be seated but we are not talking a lot of torque. I am not sure of the specs but hand tight plus 10 to 15 ftlbs of torque. Inspect the connectors to insure they are in good shape. Be gentle.

 

If you find that paper on MPG increase, let me know. Generally, multi-electrode plugs are considered just a gimmick, but it's conceivable that some users see benefits and some users see drawbacks as every engine model has a different combustion chamber configuration. I recently posted old "news" about a double tipped Denso plug that is energy efficient for sure.

Fuel efficient spark plug | PriusChat

 

The proper plug for your car is this one:

NGK (4996) IFR5T11 Laser Iridium Spark Plug,

 

OK thanks I just ordered 4...

 

Or Denso SK16R11

 

I will say there are plugs that do very well but the system I'm talking about is more than just plugs. Your going to have to get a plasma spark and will need to make and weld the proper plug design. Then of course test it. The ignition module will have be upgraded or changed out to supply the plasma. After that adjusting the fuel ratio and computer is nex. Redoing the fuel mapping to a leaner burn.

 

And what would be the point?

SM-N900P ?

 

Higher mpg. A lot depending on how lean you put it

 

Wound up searching this Denso sparkplug catalog for interchange capabilities on the cheap and cost effective and wow are there some interesting interchanges for the gen 2 Prius. Mainly started off wondering if I can use a Prius C salvage cars ignition coils and spark plugs as they seem like will do good enough in a gen 2 Prius and wondering why not like IR specs or something else spec wise.

I do see some interchange capabilities appears for the gen 2 Prius and Prius C and not certain what the differences in the vehicles performance needs and MPG's are. Everybody, any thoughts regarding?

On a side note where thinking I'll do another post regarding coils, here is what I found since pasting the above might be a little more overwhelming. Interesting however, the Toyota Parts Deal page notes that the Genuine Toyota 90919-01265 Denso FK16R-A8 only for the Prius C. Where-as the Gen 2 Prius is noted Genuine Toyota 90919-01240 Denso, of course I think is, SK16R11 with a few vehicles noted used in:

Year Make Model Trim & Engine Important vehicle option details
2012-2015 Scion xB 4 Cyl 2.4L 2AZFE; AZE151L-FHMNKA, AZE151L-FHMNKK, AZE151L-FHPNKA, AZE151L-FHPNKK
2002-2005 Toyota Celica 4 Cyl 1.8L 1ZZFE, 2ZZGE; ...
2002-2005 Toyota MR2 Spyder 4 Cyl 1.8L 1ZZFE; ZZW30L-AKGQHA, ZZW30L-AKLQHA, ZZW30L-AKMQHA
2012-2014, 2003-2008 Toyota Matrix CE, LE, S, STD, XR, XRS|4 Cyl 1.8L, 4 Cyl 2.4L 1ZZFE, 2AZFE, 2ZRFE; AZE141L-DHANKA, 2ZZGE; ...
2003-2009 Toyota Prius 4 Cyl 1.5L 1NZFXE; NHW11L-AEEEBA, NHW11L-AEEEBK, NHW20L-AHEEBA, NHW20L-AHEEBK
2006-2018 Toyota Yaris RS, STD|4 Cyl 1.5L 1NZFE; NCP131L-AGMRKA, NCP131L-...

Toyota Parts deals notes for the ignition coils for the gen 1 & 2's that the part # can be found hopefully in these potential donors (same Denso 673-1306 noted here?):
Year Make Model Trim & Engine Important vehicle option details
2004-2006 Scion xA 4 Cyl 1.5L 1NZFE; NCP61L-HHMNKA, NCP61L-HHPNKA
2004-2006 Scion xB 4 Cyl 1.5L 1NZFE; NCP31L-DHMNKA, NCP31L-DHPNKA
2000-2005 Toyota Echo 4 Cyl 1.5L 1NZFE; NCP12L-BDMRKA, NCP12L-BDMRKK, NCP12L-BDPRKA, NCP12L-BDPRKK, NCP12L-BEMRKA, NCP12L-BEMRKK, NCP12L-BEPRKA, NCP12L-BEPRKK, NCP13L-AGMRKK, NCP13L-AGPRKK, NCP13L-AHMRKK, NCP13L-AHPRKK
2001-2009 Toyota Prius 4 Cyl 1.5L 1NZFXE; NHW11L-AEEEBA, NHW11L-AEEEBK, NHW20L-AHEEBA, NHW20L-AHEEBK
2006-2011 Toyota Yaris RS, STD|4 Cyl 1.5L 1NZFE; NCP91L-AGMRKA, NCP91L-...

For the Prius C Toyota Parts deals notes (same Denso 673-1306 noted here?):
Year Make Model Trim & Engine Important vehicle option details
2012-2019 Toyota Prius C G, R, V|4 Cyl 1.5L 1NZFXE; NHP10L-AHXGBA, NHP10L-AHXRBA, NHP10L-AHXVBA
2010-2018 Toyota Yaris RS, STD|4 Cyl 1.5L 1NZFE; NCP131L-AGMRKA,...

Any thoughts regarding the plugs and possibly also the coils?

Gets me wondering about those pink genuine C fuel injectors next.

 

Ng spark plugs iridium 4 post. Gapped correctly


iPhone ?

 

Hi all, I'm about to change the spark plugs on my 2005 Gen 2, 190,000 miles. Going back through the maintenance folder, I believe it is running its original sparkplugs. The car still runs great, getting over 50+ MPG, but obviously it is high time for new sparkplugs.

I am going to get a set of NGK 4996 Iridium Laser plugs. Amazon has these, for significantly cheaper than the same set at AutoZone. Is there some way to know whether these Amazon ones are counterfit, or would they be ok to buy?

And, is there anything I should be aware of before attempting the install, especially given the age of the plugs? I have watched videos on how to do it and it seems fairly easy, with the exception of the rightmost spark plug which requires its electrical connector being unplugged first.

 

My thought is if it's not broken and getting 50mpg, why fix it?

Anything can be counterfeit now, even from Amazon. The counterfeits are so good, unless you get them from the dealer, you're playing a guessing game.

 

I hear that, why fix what isn't broken. I just figured it was well past time to change them, so I might as well do it before they fail.

 

It's up to you but spark plugs don't do much except spark. If this car was bought 2nd hand, it may have already been changed out without any records. Just don't want you to waste your time and money changing them, and then getting worse results later (this happens a lot)

 

I do think the engine runs a little rougher than it used to, and there is a little smell of gas when I first start the car, which I don't think used to happen. Could be imagining these things though; it is getting 50 MPG+ on the highway (and like 48 city) without any other obvious problems. The car was 2nd hand, but the records were thorough and there was no mention of it ever having been done. And in any case, I've put 130k miles on the car since I've had it, which by itself is way beyond most spark plug lifespans.

 

Well if you really want to do it, you should wait until the Labor sale that Toyota often has (all holidays actually). I normally shop at World Toyota in Georgia, they have an online parts catalog. Right now you would get a discounted price compared to MSRP, but if you wait until a sale, they often have 20 - 25% additional off the already discounted prices. With free shipping after $75. That's what I would do since your case is not urgent and you'll definitely get original parts.

 

Thanks JC. I may just get from AutoZone which is probably insurance enough against the counterfeit plugs issue, in case I don't want to wait for Labor Day.

Can you/anyone else comment on my other original question: "And, is there anything I should be aware of before attempting the install, especially given the age of the plugs? I have watched videos on how to do it and it seems fairly easy, with the exception of the rightmost spark plug which requires its electrical connector being unplugged first."

 

This is a very easy replacement. You would need to remove the electrical connectors on all 4 cylinders. The last one is just a little tight on space, but it can be done. Maybe you have to unbolt the Coil first so it can be slightly loose, give you some wiggle room.

I've done this many times and it's a very straight forward repair. No more than 30 minutes of your time.