OK, i searched and now am more confused than I started.

Pepboys sold me NGK Iridiums IX, part #: ZFR5FIX-11.
I have a type S.
Enter confusion: Helms manual states for Type S: NGK - PZFR6E.
So wouldn't I need: ZFR6FIX-11?

Every site I go to, sparkplugs.com and rockauto.com list the plug with the 5 rather than the 6. Is this an error?

Here is what I'm thinking:

NGK Stock Plugs
Type S: PZFR6E
Premium: PZF5F

NGK Iridium IX
Type S: ZFR6FIX
Premium: ZFR5FIX

Can anyone confirm?

 

Ok, when I changed mine, I had the same issue. I ended up putting the "5F" in it and mine's a Type-S too. I was told here that it's no big deal but I am going to change them when I get the chance. BTW, I have not had ANY problems with it since it's had the 5F's in it.

 

Im pretty sure one just burns alittle hotter, but as he said it should be no big deal. Sorry I can't help with which one is correct for the car

 

I looked at the Pep Boys computer and some years show the same plug in both p and s. They didn't carry the 6's when I bought mine so when you ask for a Type S plug they'll just give you a P plug, they don't know the difference.

The higher the number the colder the plug. The S needs a colder plug because of the higher heat it makes from the higher compression than the P. If you use a plug that's too hot it could pre-ignition and loss of power. You'll probably never notice it because the computer pulls timing out until it stops. Same thing happens when you use a lower octane gas.

If you have a Type S get the 6's, unless you don't care about the slight loss of HP.

 

that's what i figured.

i just did a double take, because not only pepboys, but every single website online lists the same plugs for P and S.

i plan on going with the colder plugs.

thanks guys.

 

When I was searching for them at my local parts stores, every place had to special order the 6's. WTF! That's why I ended up going with the 5's not too mention because I couldn't find a straight answer on the forum.

 

Exactly. The above is confirmed. Along with these:

DENSO (according to helms)
Type S: PKJ20CR-M11) (IK20)
Premium: PKH16CR-L11 (IK16)

BOSCH Platinum +4 (according to bosch website)
Type S: 4417
Premium: 4418

I understand why some would say it does not matter, but there is a reason why there is a difference between models.