Denso spark plugs?

[mclemore102]

What is the correct part # for the denso spark plugs for our trilogy cars?

[fastblackmerc]

Per Sgt. Mac and this post: http://www.mercurymarauder.net/forums/showthread.php?t=27420&highlight=denso

IT-20 for N/A cars, IT-22 for supercharged.

[mclemore102]

Ok thanks! So IT-22 plugs for supercharged cars. What is the correct gap for them?

[fastblackmerc]

Don't know the gap setting, I believe they are pre-gapped. Found this doing an internet search:

"Install note: The iridium center electrode is very thin. Unlike a conventional plug, you cannot gap the plug by sandwiching a gap tool between the electrode and the ground strap, then pushing on the ground strap. The hard electrode will dig into the gap tool, and when you remove the gap tool, you'll break the electrode. Instead, adjust the ground strap by tapping it on a hard surface, or by pulling it gently with a tool; then measure the gap using your gap tool."

I'd check with the vendors on the site that carry the plugs.

[mclemore102]

Ok thanks!

[greggash]

Here is a picture of the denso's I had in my car for about 20k

Sorry its an attachment, but mine were probably toast after 10k miles.

In the picture you can see I was leaking compression arround the porcelin insulator

[SergntMac]

Greggash...That brown stuff around the porcelin is not a sign of leaking compression. It is how all Denso plugs look after some use with OEM boots and connectors.

I have installed and removed Denso plugs from 3 Marauders now, and all of them have looked the same. Just like that in your pic. Rubs off, no problem. Try a shot of WD40, they clean up nice.

[fastblackmerc]

Try a shot of DW40, they clean up nice.
Or you can WD40.... JK SergntMac... :D

[SergntMac]

Or you can WD40.... JK SergntMac... :DLOL...My bad, fat digits...Thanks!

[KillJoy]

Greggash...That brown stuff around the porcelin is not a sign of leaking compression. It is how all Denso plugs look after some use with OEM boots and connectors.

I have installed and removed Denso plugs from 3 Marauders now, and all of them have looked the same. Just like that in your pic. Rubs off, no problem. Try a shot of WD40, they clean up nice.

Anyone have any idea what this is, or what causes it?

KillJoy

[mclemore102]

Would it be worth changing from the motorcraft plugs to the denso plugs?:dunno:

[Bradley G]

I would stay with the Motorcraft.
Gap .032 - .035

[RF Overlord]

^^^what Bradley said^^^

[BigMerc]

I have used both, I would use Motorcraft or NGK but not denso's, they were gone long before what the purchase price was worth.

[ap2003]

Uhhmmm... Fron the Denso site...
http://www.densoiridium.com/find_part.php?type=auto&autoYear=2003&make=MERCURY&action=Search

Says there... IT16 (for NA).
Is the IT20 for the Rienhart stage 1?


BR
Gus

file:///C:/DOCUME%7E1/app/LOCALS%7E1/Temp/moz-screenshot.jpg

[MM03MOK]

Is the IT20 for the Rienhart stage 1?
Yes .


IT-20 for N/A cars, IT-22 for supercharged.

[fastblackmerc]

Anyone have any idea what this is, or what causes it?

KillJoy
I think it's just dirt accumulation. Since the spark plug / coil boot doesn't go all the way down there is nothing to protect it from dirt. I've seen this on alot of cars....