Spark Plugs....

[fedyfedz]

Going to change spark plugs coming up on 100k My question is what is the correct torque spec for the spark plugs. Ive been reading mixed answers online some say 18ft some say 13-15ft, what is the correct torque spec? Can this job be done without a torque wrench? If so I would assume you would want to put equal amount of turns to make each plug same tightness. Sorry if this is newbie question. Also is it better to do when engine is cold or hot. Also should I disconnect battery for this job?

 

[Joe Dirt]

I did mine when the engine was warm, battery hooked up still (no harm) and I just guesstimated on the socket handle. 12-18lbs. isn't much though, so don't go nuts with them.

 

[fedyfedz]

great thanks can always count on you to reply with very helpful useful info

 

[Limited02]

***Make sure that you put anti-seize on the threads of the spark plugs*** so they don't stick to the heads!!! Also, if you have an air compressor, take the COP off and blow air down into the hole before taking the plug off. You'll get a lot of crap out of there and it'll make it easier to install the spark plugs

When I tighten mine after putting anti-seize onto the threads of the spark plug, I snug them up till it stops and give it about a 1/4 turn.

 

[fedyfedz]

great thanks, will attempt to tackle tomorrow i bought anti-seize and dielectric grease for the coilpack connections.

 

[EasyRhino]

The spec is 18 ft-lbs for all 2002-2005 and 2006 and later V6s, and 25 ft-lbs for 2006 and later V8s. Ignore the 1/4 turn advice. These are not crush-washer type plugs.

These are aluminum heads - DO NOT do this job unless the engine is completely cooled down. Doing this job hot and not following torque specs risks the dreaded spark plug blow out which will occur later.

Also, do not use anti-sieze on these threads - controversial but factual.

Good advice on blowing out the spark plug bosses with compressed air before removing the plugs to ensure that no trash winds up in your engine or in the spark plug threads. And a late edit - if you pull the coil packs several hours before removing the old plugs, you can put a few drops of penetrating fluid down in the spark plug bosses to work on the threads before you put a wrench to them. On a good day, it just might help prevent a little steel to aluminum thread tear out on known weak heads.

I strongly recommend use of soft rubber tubing to initially get the new plugs to thread in - it's way too easy to cross-thread these plugs if you use the socket and extension to line up the threads initially. The soft robber hose prevents this possibility, ensuring that the threads are aligned correctly.

Lastly, use only the factory plugs, these engines are recognized to respond poorly to aftermarket plugs. And put a glob of dielectric grease into the coil boot that mates with the plug before replacing it onto the plug. Always unhook the battery just for extra security - these electronics are sensitive - why risk it?

Overall, it's a surprisingly easy job, but offers lots of opportunities to bugger up your heads if not careful.

 

[imp]

......Also, do not use anti-sieze on these threads - controversial but factual........

Any technical info on why not?

Seems since plugs are invariably steel, and the dissimilar aluminum head material is prone to galling, etc., that a long-term lubricant would be useful there. imp

 

[waskly]

never had a plug blow out from anti-seize, i still use it to this day. makes it so much better the next time around.

 

[EasyRhino]

Any technical info on why not?

Seems since plugs are invariably steel, and the dissimilar aluminum head material is prone to galling, etc., that a long-term lubricant would be useful there. imp

I hear you loud and clear and that would be my default position; however, when I went to do this job on mine and researched on line, I found evidence to the contrary.

Now I am an engineer for many years and am 'addicted' to understanding of materials and avoidance of galvanic corrosion, etc. so I was surprised.

However, since this was a once in a lifetime job for me on this vehicle, I did not preserve the evidence.

I did find much of my early search evidence on this website, although it led to others as well. Perhaps someone else here kept the evidence or knows where it is.

Still odd, I admit. I think it came down to the fact that lubricating the threads (which anti-sieze would accomplish, even inadvertently) led to over-torquing, which in turn led to thread tear-out, which can lead to lug blow out, which leads to head removal/repair/replacement.

In may in fact be due to the head design being such that the threads are too close to the tear-out margin that one has no choice but to avoid anti-seize even though it would normally be the right thing to do.

 

[EasyRhino]

never had a plug blow out from anti-seize, i still use it to this day. makes it so much better the next time around.

I hear you, but I avoided it in the case of these heads that are known to blow out. Most others are not known for this problem.

I have used anti-seize on every since dissimilar metal fastener I have installed over the last 30+ years.

See my prior post on a possible rationale why.

 

[fedyfedz]

ok so good and bad, good is i got the job done in about 2 hours bad is the plugs were horrible and on the plug on the driver side closet to cabin had oil in it and plug was soaked, used compressor and blew air in and around before removal.

Heres where i need help, after i started it up sounds like a misfire almost like a chopped put put when at idle, driving normal feels and sounds better than before, but when i come to a stop i feel the choppy rumbleness (excuse my poor desrcibing method) the service engine soon light came one after 20-50 miles i didnt pull the code yet waiting for my friend to come home with scanner. well any way heres some pics of the plugs

horrible

 

[69Explorer69]

did all that debris come out of your engine or did you lay the plug down then picked it back up to take pics

 

[fedyfedz]

Unfortunetly thats what they looked like when i pulled them i used an air compressor to clear all shyt away first also

 

[imp]

Unfortunetly thats what they looked like when i pulled them i used an air compressor to clear all shyt away first also

If the shiny, fine silvery particles in the threads are scrapings of aluminum from the head, not good from the looks! Plug holes can be re-worked, no doubt, if insufficient thread appears to be left, but in any case, you surely do not want to experience the plug "blow-out" of the head altogether, as described elsewhere in the forum! imp

 

[EasyRhino]

ok so good and bad, good is i got the job done in about 2 hours bad is the plugs were horrible and on the plug on the driver side closet to cabin had oil in it and plug was soaked, used compressor and blew air in and around before removal.

Heres where i need help, after i started it up sounds like a misfire almost like a chopped put put when at idle, driving normal feels and sounds better than before, but when i come to a stop i feel the choppy rumbleness (excuse my poor desrcibing method) the service engine soon light came one after 20-50 miles i didnt pull the code yet waiting for my friend to come home with scanner. well any way heres some pics of the plugs

horrible

The look of that plug frightens me. Since you blew it out, I too am thinking that you may be looking at bad aluminum threads in your head on that cylinder. Be very, very careful if that's the case and avoid threading/unthreading that cylinder as much as possible.

It looks like that electrode is pretty decent. With these heads being so weak, I am beginning to grasp the argument on this forum to leave them in for life, as the threads may be a weaker point than living with old plugs. (to recap my prior comment on use of anti-seize).

Anyway, if that plugs has not been 'ejected', I think that your problem may not necessarily be related to that plug, but to coil pack connections or, as was my case, a poorly hooked up fuel injector log after I swapped the plugs. I don't wish to send you on a wild goose chase but your description of the way yours is running sounded similar to mine after changing plugs, and in my case it was not making sure that the injectors were back in correctly.

Good Luck.

Re-reading your thread it sounds like all/many of your plugs looked that ugly. I'm also wondering about the oil soaked discussion - was that on top of the plug or on the electrode end?

 

[fedyfedz]

it was on the electrode end and i beleive it sand/debris on the plug it did not look like metal, on of the plastic connections is missing the clip to hold it on to the coil but i zip tied it for now and checked to see if all of the connections were on and the coil packs were pushed down enough. seemed to be in my eyes

 

[fedyfedz]

the plastic connector the houses the wires to be plugged into the coil has a little tab ur supposed to press to release. does this have to have the clip becasue i believe to are missing the clip but they are firm on there. If I would need new clips would i just have to cut wires then run them into new clips, i dont think that this is the problem, im scanning the truck today when i get home :/

 

[wicsmith1997]

You did check the gaping of the plugs before installing them right? Been my experience no plugs I've purchased has been properly pre-gaped.

 

[fedyfedz]

All of them were pretty spot on and anyones that were slightly off were corrected

 

[Limited02]

If you're having a misfire, it's possible a COP is going bad. Very common It may not be as noticable when accelerating, but could be more pronounced when idling.