Anyone tried using the Ruthenium HX Spark Plugs on the V8 LS?

DaleGrib

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External oil leaks do not foul plugs. Internal oil consumption could (bad rings, bad valve stem seals, PCV fault, ... ).

Leaking valve covers can, over time, degrade the coil boots and cause some problems. In the early days when the LS misfire issues were first noticed, they discovered that the valve covers gaskets were leaking oil into the spark plug wells, and assumed that was the problem. Later, they discovered that the main problem was that the epoxy in the coils was failing and causing high voltage breakdown in the coils.
The oil leaks needed to be solved (and eventually were), but they had only a little to do with the misfire problem. It took even longer, but the coil problems were eventually solved too.

If your misfires are on specific cylinder(s), then it would be best to change the coils and the plugs at the same time. The current OEM coils should outlast the rest of the car...
 
External oil leaks do not foul plugs. Internal oil consumption could (bad rings, bad valve stem seals, PCV fault, ... ).

Leaking valve covers can, over time, degrade the coil boots and cause some problems. In the early days when the LS misfire issues were first noticed, they discovered that the valve covers gaskets were leaking oil into the spark plug wells, and assumed that was the problem. Later, they discovered that the main problem was that the epoxy in the coils was failing and causing high voltage breakdown in the coils.
The oil leaks needed to be solved (and eventually were), but they had only a little to do with the misfire problem. It took even longer, but the coil problems were eventually solved too.

If your misfires are on specific cylinder(s), then it would be best to change the coils and the plugs at the same time. The current OEM coils should outlast the rest of the car...

I changed them all at the same time before. I had the leak with oil getting into the spark plug wells before because the guy didn't do a good job changing my valve cover gaskets. I know I kinda doubt it's the plugs as well but I want to at least have them taken out and cleaned up and replaced with good new plugs just to be on the safe side. And the misfire is never picked up by the computer as no codes are pending or active for any misfires. I was going to just go ahead and have the plugs done and then possibly pay someone else to finish troubleshooting it if the problem still remains after. Cause I also still have P0451 as an Active code and I doubt that is the cause of this misfire as well. (Also I did resolve the oil leak with the valve covers or I know I would or could be wasting my time)
 
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I am just gonna take it to a shop and let them figure out the issue. Also gonna let them do the Fuel/Air Induction Cleaning service to clean everything up a bit. They are going test compression and all to see what the issue really is.
 
Yeah... good grief why? You could buy 4 OEM platinum ... or 2 iridium plugs for the price of 1 ruthenium.

I have over 150k miles on a set of Bosch iridium plugs... with no issues, and only 1 replacement boot set on the car... now at 230k plus.
 
Yeah... good grief why? You could buy 4 OEM platinum ... or 2 iridium plugs for the price of 1 ruthenium.

I have over 150k miles on a set of Bosch iridium plugs... with no issues, and only 1 replacement boot set on the car... now at 230k plus.

Well, in the end, I would try to go with the best since I am considering replacing the coils is why. I mean when you're already spending dang near $400 on coils why not put what they rate the best long as no one has anything bad to say about them other than the price. I know it might be a good bit more price wise for the ruthenium plugs but trying to keep everything clean and running as good after I have the fuel/air system cleaned, and the motor compression tested. I am having that cleaning done and resolving that P0451 code then will know for sure if I need to replace plugs/coils. I plan to drive this car for a very long time so I want to baby her and spoil so she does not screw me over. Also, they are on sale right now for $7.78 each and the NGK Iridium is $8.36 right now.
 
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RA has the ruths for $8.50 and the irids for about half that. Heck... the platinums will get you 100k for about $2 each. Guess it depends on how many miles are on the LS now. At 230k I won't be putting $8 spark plugs in mine. I'll consider myself fortunate if it makes it to 260k... and very happy if it goes to 300k

Sometimes it's not the milage,,, but the age. At least thats what my body is telling me. :D
 
I think the ruths were designed for longevity... not performance. Maybe more so for vehicles where the plugs can be hard to get to. Not an issue on the LS, (unless you have the V6)?
 
I think the ruths were designed for longevity... not performance. Maybe more so for vehicles where the plugs can be hard to get to. Not an issue on the LS, (unless you have the V6)?
I have the V8 but according to the google.
NGK has created the Ruthenium HX spark plug, which is designed for maximum durability and performance. According to NGK, the spark plugs burn fuel more completely than other precious-metal plugs, providing for a quicker throttle response, smoother idle and better cold starts.
 
There's no performance gains from those plugs. The NGK Plats are what most LS owners put.

FYI, gaps play more of a role than plug tips. But usually gaps are changed if you go forced induction (thin the gap).

Run the NGK Plats, swap out after 60 to 80k.

Edit: If you don't even have a tune in that LS, I wouldn't bother looking at 'performance' gains, as you're not gonna see it. First, get a SCT Xcal 3. Get one used with minimum 3 unlocks left. Then contact Torrie @ Unleashedtuning. Get a street tune on that baby. Better money spent than high end plugs.
 
I am gonna give them a shot, I mean all their descriptions online say they are performance plugs.

NGK RUTHENIUM HX™ is born from advanced OE technology as a high ignitability spark plug available in both DFE (Double Fine Electrode) and PSPE® (Projected Square Platinum Electrode) tip designs. Higher performance and reduced misfires are key to today’s modern engines. NGK RUTHENIUM HX™ provides a more complete fuel burn by igniting a wider range of air-fuel ratios which offers improved performance in rich or lean engine conditions. With NGK patented Ruthenium technology, NGK RUTHENIUM HX™ provides unparalleled durability and performance for today’s modern vehicles.

Sounds good to me even if I don't notice anything different far as performance goes. If what they say is true about them providing a more complete fuel burn, then that sounds good to me. And NGK has never let me down, ever! So I will give them a shot.
 
Let me know if its worth trying....I was thinking about it just yesterday. Wont do my plugs until early may though.
 
Thanks joegr! I learned something new today. I had always heard and recommended that oil getting into the plug wells was the root cause of misfires and coil break down. I did not realize they finally traced it to the coils themselves.

I was very pleased when Ford gave the 10 year/100K extended warranty on the coils and cam cover gaskets. I was surprised but they covered that twice on my old 2003 V8 Sport.
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I almost bought those plugs but I ended up going with the next step down just because of cost.
 
What!!! When did that warranty ran out?

The extended coil warranty?
100K miles or 10 years, whichever comes first. 2006 was the last model year for the LS, and the last LS probably sold in 2007, maybe 2008, so that warranty has been expired for all of them for years now.
 

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