3.2L: What non-OEM plugs do you like or have success with?

chitownV · Post by **chitownV** » 23 Jul 2020, 18:17

The part packaging is printed for MY 11+. So the Denso still not for the earlier 3.2s. FCP says it should be the NGKs for earlier years if going aftermarket. So best to check with chassis number.

Unless I am buying from a reputable place like FCP, I like to get the original Volvo because iridium plugs in general have counterfeits. I get the original Volvo ones because I have already warrantied my first set from FCP and don't have to worry about purchasing counterfeit spark plugs.

Just as a clarification, in my post about plug gap, when I was referring to twin tip design blocking the spark, I meant the twin or more electrode designs.

Post by **pgill** » 23 Jul 2020, 19:45

Post by **pgill** » 23 Jul 2020, 21:10

chitownV · Post by **chitownV** » 23 Jul 2020, 21:41

Good work. Oh I am not disagreeing with you, even FCP carries it. I am trying to understand why Volvo would have separate types of spark plugs for early models, then 2011+ have a different set of spark plugs. Also, why wouldn't a place like FCP say the Densos can work with the earlier models. Not sure if there is an engine programming difference.

I am very very well versed in spark plugs from experience. That said, I have seen some engines run worse with iridium plugs versus traditional plugs. I have also seen resistance in plugs change over time and the non-factory-branded plugs' resistance increase as updated plugs are released. Even FCP will sell non-factory plugs that don't work as well in some vehicles because that's what is in the plug manufacturer catalogue. However, both NGK and Denso spec'd for the 3.2 are iridium. I checked the plug specs, and they are both the same. The heat range shows different numbers, but that is because each brand uses a different scale. I cross referenced and it is the same heat range.

Like I said, I cannot comment on using the Denso since I have not used them, thus I don't. Seeing this though, I might have to lighten the wallet and try them out. I am at 152k miles so I just changed the spark plugs in the last couple thousand miles so comparison would be to pretty new Volvo plugs (p/n 31216183).

What I want to see is the real timing data with the different plugs. I want to check with the Densos if timing does not get pulled as much (like when it is hot outside or using 87 octane gas) and if it can advance more often (for more power), or if it will be the same. If the only experience with the Densos are after someone has changed worn out plugs (regardless of brand or model), then the comparison isn't really comparable.

Post by **pgill** » 24 Jul 2020, 10:05

chitownV wrote: ↑23 Jul 2020, 21:41 Good work. Oh I am not disagreeing with you, even FCP carries it. I am trying to understand why Volvo would have separate types of spark plugs for early models, then 2011+ have a different set of spark plugs.

The answer to you question is availability

In 2007 the Denso SIP was still new and unproven

So the Engineers in the Premier Automotive Group chose the simpler fine tip Iridium.

This was the conservative safe choice.

By 2011 something changed the minds of the Engineers.

Note: the 3.2 design didn't change significantly

So for me I am choosing to use the latest design that was qualified by the Volvo Engineers.

Having said that any of the spark-plugs from the picture in the post above should work fine.

My Goal is to make it to 300,000 mile on the original coil packs and original catalytic converters.

: Denso_timeline.jpg (110.98 KiB) Viewed 2505 times

chitownV · Post by **chitownV** » 24 Jul 2020, 12:24

pgill wrote: ↑24 Jul 2020, 10:05 Having said that any of the spark-plugs from the picture in the post above should work fine.

My Goal is to make it to 300,000 mile on the original coil packs and original catalytic converters.

Denso_timeline.jpg

Though I have not used the newer Denso plugs, I can agree based on the specs. NGKs and original Volvo branded ones too. Buy from FCP and you can warranty them when the time comes.

2000c70hpt · Post by **2000c70hpt** » 25 Jul 2020, 16:29

Mine had the original FoMoCo plugs in mine after 180k. Xc90 still ran smooth as silk even with those old plugs. Threw some denso iridium in and she livened up a bit. Fuel milage is better though. I used the stock gap

chitownV · Post by **chitownV** » 25 Jul 2020, 16:33

I would assume for over worn stock plugs any new plugs would improve overall performance. Good to hear the Denso iridium plugs are working for you.

2000c70hpt · Post by **2000c70hpt** » 25 Jul 2020, 16:50

Yes so far so good

Post by **pgill** » 25 Jul 2020, 19:31

2000c70hpt wrote: ↑25 Jul 2020, 16:29 Mine had the original FoMoCo plugs in mine after 180k. Xc90 still ran smooth as silk even with those old plugs. Threw some denso iridium in and she livened up a bit. Fuel milage is better though. I used the stock gap

200c70hpt,

180,000 on the original spark-plugs.......that's a really long way to go

I will be on my fourth set by the time I get to that many miles.

Based on my personal experience owning two 3.2's and from what I've read on the forums any of the Denso Iridium or Denso Iridium Twin Tip will work very well in the 3.2

If you prefer you can buy the Spark Plugs in the Volvo Packaging and pay a little more
(as you can see from the picture I posted above the Volvo Spark Plug has the Denso Part number on it)

Based on my personal experience with my friends Toyota the Denso Iridium Twin Tip are helpful in eliminating the Catalytic Converter efficiency code (P0420)

I can't say for sure why the TT's worked but if I had to speculate it is due to superior ability to ignite a lean mixture.

The ECU adjusts the mixture and it checks the response of the O2 sensors before and after the catalytic converter.

So for my $$$ I'm getting

IKH20TT
or
FK20HQR10 --> (you can buy these in a Volvo box p/n 31286359, just remember your Volvo is a 2011 3.2 or newer)

Note: there is nothing wrong with the regular Iridium spark plugs

I change mine every 50.000 miles

3.2L: What non-OEM plugs do you like or have success with?

Re: 3.2L: What non-OEM plugs do you like or have success with?