Spark plug help strikes again
- Thread starter tallrd
- Start date
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- MP5T / 944
Extreme Heat will cause that.
Loose the Iridium and go with OEM Copper.
Loose the Iridium and go with OEM Copper.
Yes definitely ditch the iridium... I run NGK BKR6E's with good luck... the plug is generally a bit hot, but not too too bad... doesn't show det marks but it is a little fuzzy right where I need to see.. keep in mind if you were highway cruising right before you pulled the plugs that they will look more "lean" than if you pull them right after boost... like literally take a new set of plugs and right in the middle of boost shut the car off and coast to a stop and pull and read the plugs... that is the most accurate way of checking plugs for each condition (hit the desired condition and then shut the car off in the middle of it and then read the plug).
These are the one's which were in the car when I got it back in Feb, so I've never changed them on this car. Can you tell that those are iridium just by looking?
PZFR6F-11 is the OEM plug; Assuming the plugs I have are iridium as you say, are you also saying that will be better even factoring in the mods I've done?
PZFR6F-11 is the OEM plug; Assuming the plugs I have are iridium as you say, are you also saying that will be better even factoring in the mods I've done?
Shawn... I'm just about positive that Chris didn't put Iridiums in there... so I'm guessing they are the stock platinum's unless Eric who owned it before Chris put them in there... I didn't even realize it was you that posted... I was just responding to the info... I just assumed Brian was right... But I know Chris didn't put Iridiums in there.. I would have beat him sensless had he tried.
Yea, I had the EXACT same coloration on mine after moving my MAF. So I stepped it down a notch and everything is fine. Most likely you are too lean. Are you boosting in 5th alot?
Also, I noticed that you are only boosting 8psi? I figured with all those mods you would have been a little more brave.
Anyways, your system isn't too hot like mine was before I upgraded the SMIC because you have a FMIC and if anything, it would be too cold.
I have to agree with FlyinMSP on this one, your map is probably too lean for your car.
Also, I noticed that you are only boosting 8psi? I figured with all those mods you would have been a little more brave.
Anyways, your system isn't too hot like mine was before I upgraded the SMIC because you have a FMIC and if anything, it would be too cold.
I have to agree with FlyinMSP on this one, your map is probably too lean for your car.
Thanks for the help guys. I appreciate it.
What would your responses be if I were to tell you that I often backfire from running too rich? Is it possible to be rich enough to backfire daily, but so lean as to make the plugs look like they do? I'm more inclinded to believe it's a temp related issue and not so much an A/F issue.
Thoughts?
p.s. DAWIV: I'm not sure which plugs those are, but I'll look later tonight.
What would your responses be if I were to tell you that I often backfire from running too rich? Is it possible to be rich enough to backfire daily, but so lean as to make the plugs look like they do? I'm more inclinded to believe it's a temp related issue and not so much an A/F issue.
Thoughts?
p.s. DAWIV: I'm not sure which plugs those are, but I'll look later tonight.
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DAWIV said:
I don't see any blistering.. and they aren't TOO super hot... if they were the base of the plug threads will turn white as well... the fact is there is even some brown on the flat of the ground tip which is in and of itself an indication that these plugs are not really running all that hot or all that lean.
While these are showing slightly lean and hot, that could easily be just solely off a recent highway cruise as the car will run very lean and rather hot during that time... which is a whole different ball game than what happens in boost.
EDIT:Backfiring and popping is somewhat common if you have deleted at least one of the cats... I know you have the corksport exhaust... so I'd check to see how many other people are getting similar popping given the mods you have.
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I'll try and pull some plugs out of my car and post them for you as well.. I can tell you that my car never runs leaner than 14.8 unless I'm decelerating.. and in boost I'm under 12.2 AFR at all times... You'll see a similar pattern and appearance on my plugs I'll bet... and I'll bet that your level of white is from highway driving and so forth..
Also, keep in mind that a lot of the "plug charts" you see online are from distributor based vehicles and many times culled from carbed cars which never run as lean as the more modern EFI systems.
Also, keep in mind that a lot of the "plug charts" you see online are from distributor based vehicles and many times culled from carbed cars which never run as lean as the more modern EFI systems.
tallrd said:
Rich at idle and lean under boost would be my first guess. My car does the same thing. When you are boosting, the air mixture is cleaning the plugs.
Do you have an FCD? Try driving for a day or two without boosting (if that is possible) and check them again. If they are sooty that is your problem.
Good luck!
Yeah... I agree with genius... do that test and that'll help a lot. try to restrict to stop and go in town traffic too if you can.... interstate style driving will heat a plug a lot as well because you will sometimes lean out to about 16 or 17 AFR on the highway for fuel economy in many cars.
tallrd said:
A very dangerous toy for your motor... basically eliminates fuel cut by clamping voltage from the MAF... as the air input rises the voltage stays at a same peak... engine leans out... detonation starts... go too far.. go boom.. That's what an FCD is...
But a JandS has a similar feature except that a JandS will also pull timing and protect from detonation and then your motor and car will be fine.. and you'll see it light up like a christmas tree and know you need to back off.
Although i can see there may be benefit to adding something more to my car, I really don't *want* to add anything more. I believe that my current setup has the components to make a wonderfully tuned car. I just need to educate myself a little on how to do it properly.
Should I:
A) get a dyno and go into the brain of the AFC unit to compensate a/f's there? If so, who out there can help guide me b/c DSM sure isn't helping me...
B) get new plugs, or
c) both, or
D) none of the obove.
Should I:
A) get a dyno and go into the brain of the AFC unit to compensate a/f's there? If so, who out there can help guide me b/c DSM sure isn't helping me...
B) get new plugs, or
c) both, or
D) none of the obove.
