USE DIELECTRIC GREASE ON SPARKPLUGS

fmorelli

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Not to the degree you described. I've had oil residue and carbon in the spark plug tunnel. I always torque my plugs as well. I am suspicious of the single-use crush aluminum washers, and those disappeared when I went to the N20 plugs. I clean the tunnel to where it is perfectly spotless, especially the base where the spark plug washer mates to the plug face on the head. This can take a while - carb/injector cleaner and a long, thin-tipped flat blade screwdriver (called carburetor screwdriver for us old guys) pushing a long, thin piece of cut rag. Obviously don't mar the head. This ensures the plug washer seats completely flat, and allows you to monitor any leakage going forward.

My experience, above, is not conclusive to me. Just my suspicion from what I've observed.

Spark plug change in the auto store parking lot, in the rain - that sucks.

Filippo
 
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Jeffman

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It’s certainly possible. Check Filippo’s comments above. Clean the plug seats. Use the plugs with copper crush washers. Torque. Retorque a week later.
 

Rob09msport

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I had the zr5tpp33s which I think are n20, i went to 97506 simply cause it's all i could get was pouring and i was trying beat the sunset lmao. Plus I was committed cause first store lost my plug I gave them , not that my OCD would allow reinstall anyway. I think I need to clean the tunnels better and also make sure the slit in the insulator on the engine is facing down I think is a good idea . I am going to rig some type of tool that i can have insert into spark plug hole and have a shoulder doi cleaning to avoid debris in engine. Normally I crank once but push to start scares me too try that method. I had big scare thinking that sonething was cross threaded but threads looked perfect and I went to 20 lb instead of 17. The store said a brown ring on ceramic means leaking and is more common than you think. DSM guys seem to be only thing I found with quick search that had any substantial leak.
Btw my tips were perfect and now I have no corrections on high boost low rpm or for most of my drive to work which everyone knows is common to have low load corrections. It def seems to be helping as far as that goes I'll log today I just never jump into high rpm high load right away.
 

typedRew

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Just to add my extremely minor contribution here.

I pulled my plugs to inspect them, cleaned them up and reinstalled everything with a dab of grease in the boot and just shoved it down over the plug, not the right way but my way. lol

I installed everything back the way it was, i changed nothing, no new flash, no reset of adaptations. Nothing. Ever since then the car feels stronger, now that is subjective but what isn't is my mpg. It seems to be much better than before. I'm not going to post my complete results until I get another tank of fuel under my belt, but as of now, it seems to be at least 3-4mpg better with no changes. On a car that is extremely consistent with its poor mpg I find this to be a massive benefit. Hopefully it keeps up, will post again when i've ran some more miles with it to confirm.
 

Rob09msport

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Just to add my extremely minor contribution here.

I pulled my plugs to inspect them, cleaned them up and reinstalled everything with a dab of grease in the boot and just shoved it down over the plug, not the right way but my way. lol

I installed everything back the way it was, i changed nothing, no new flash, no reset of adaptations. Nothing. Ever since then the car feels stronger, now that is subjective but what isn't is my mpg. It seems to be much better than before. I'm not going to post my complete results until I get another tank of fuel under my belt, but as of now, it seems to be at least 3-4mpg better with no changes. On a car that is extremely consistent with its poor mpg I find this to be a massive benefit. Hopefully it keeps up, will post again when i've ran some more miles with it to confirm.
Def is real. When I was kid we had a dodge ram SUV and that thing would feel like an animal when it got new plugs distributor and wires. Reason is you gradually lose little bit performance and then abruptly get it back. It's like a kid after a year the parents dont really notice them growing but someone that didn't see them for yr notices the growth.
 
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typedRew

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Id also like to state. Ive had two sets of plugs in this car since i've owned it. I also clean them every oil change(why i had them out to clean them the other day) Completely swapping them with new units, or cleaning them(new coils also) has never resulted in such a massive gain in mpg, in fact I haven't ever improved mpg with anything ive done to the car yet.

Which is why this is such a massive shock.
 
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Rob09msport

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Could you have just accidentally infected m indexed and maybe it does make difference on di cars idk
 

typedRew

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Possible sure, i've never indexed a spark plug purposely in my life, so i wouldn't know for sure.
 

Itsbrokeagain

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I doubt indexing would seriously affect the way the cylinder runs. We arent talking 10,000 hp top fuel dragsters here.

On another note, i had similar issues with cylinder #2 and it kept dropping out on E30 mix. I took the plugs out and regapped them but noticed the burn ring around the bottom of the porcelain right where the boot sits, along with the one on cylinder 5. both were finger loose when I removed them. Even torquing them back cylinder 2 still misfired.

We were running on an original PR kit, all my connections are solid, so we switched from the 5992 to 97506s and we had 2 nights on an E30 mix again where the car ran phenomenal...then the following day it dropped #2 again cruising along in traffic. This was after the dielectric grease was applied (sparingly).

After some emails with Tony and @V8bait , turns out running a double barrel kit on the street with 93 or a mix of 93 and E85 and hitting 3,600psi rail pressure on pulls and 80+ on the LPFP side, is not so great for the injectors, and we believe the #2 injector is taking a dump. Its an index 12 and less than 3 years old, but Justin recommended to disconnect one pump for the time being if we are mostly running on the street as the shotgun pump on full E85 should support 600-650hp without an issue. With both pumps running and the Stage 3 twin intanks at full power, we have enough for 800 and more boost but either the clutch or the axles are going to take a dump after that.

At some point next year Im going to upgrade the LPFP line from the tank to the engine with a -6 line or something to allow the pumps to breathe a little more.
 

Rob09msport

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I doubt indexing would seriously affect the way the cylinder runs. We arent talking 10,000 hp top fuel dragsters here.

On another note, i had similar issues with cylinder #2 and it kept dropping out on E30 mix. I took the plugs out and regapped them but noticed the burn ring around the bottom of the porcelain right where the boot sits, along with the one on cylinder 5. both were finger loose when I removed them. Even torquing them back cylinder 2 still misfired.

We were running on an original PR kit, all my connections are solid, so we switched from the 5992 to 97506s and we had 2 nights on an E30 mix again where the car ran phenomenal...then the following day it dropped #2 again cruising along in traffic. This was after the dielectric grease was applied (sparingly).

After some emails with Tony and @V8bait , turns out running a double barrel kit on the street with 93 or a mix of 93 and E85 and hitting 3,600psi rail pressure on pulls and 80+ on the LPFP side, is not so great for the injectors, and we believe the #2 injector is taking a dump. Its an index 12 and less than 3 years old, but Justin recommended to disconnect one pump for the time being if we are mostly running on the street as the shotgun pump on full E85 should support 600-650hp without an issue. With both pumps running and the Stage 3 twin intanks at full power, we have enough for 800 and more boost but either the clutch or the axles are going to take a dump after that.

At some point next year Im going to upgrade the LPFP line from the tank to the engine with a -6 line or something to allow the pumps to breathe a little more.
Wait so the injector is causing plug to get loose Is the theory?
 

Itsbrokeagain

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Wait so the injector is causing plug to get loose Is the theory?


Apparently if the cylinder misfires and fuel is shut off, the pumping action of the cylinder will unseat the sparkplug and work it loose. On the two cylinders giving me issues I had a lot of carbon or blowby in the spark plug well.
 
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Jeffman

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Apparently if the cylinder misfires and fuel is shut off, the pumping action of the cylinder will unseat the sparkplug and work it loose. On the two cylinders giving me issues I had a lot of carbon or blowby in the spark plug well.
That’s amazing! First time I ever heard this. Anyone else ever hear of misfirings causing spark plugs to loosen?
 

Itsbrokeagain

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That’s amazing! First time I ever heard this. Anyone else ever hear of misfirings causing spark plugs to loosen?

I read it somewhere on here or one of the N54 forums. It happened twice with new 5992s...torqued down to 17ft lbs and the same two cylinders misfired. 20 min later I get to pulling the plugs and sure enough, both come out with barely a twist of the rachet. I made 100% sure all the threads and seating surface were clean of debris.
 

Jeffman

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I also recently reported loose NGK 5992 = NGK 95770 plugs when I had misfires, despite torquing them to 17ft-lbs. Damn! So that means excess pressure in the cylinder from the misfire essentially results in a loosening torque on the plug. Sounds like everyone’s having this problem.

So what’s the solution to N54 plugs loosening?
Thread locker? (LOL!)
 
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fmorelli

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I've not had the issues in the past couple thousand miles, since I switched over to the plugs with copper (solid) "crush" washers. But a couple thousand miles is low evidence at best. I know of no thread locking solution. Some might say threads in the head are worn - but my car was in the 20k's when I had the issue, and $300 calibrated torque wrench on the 95770 plugs.

My thought, thus far - super clean the tubes, make sure threads are clean (head and plugs), torque to spec. I think we need to start with well-known baseline and see where it goes from there. I can't vouch for what my situation was prior to the issue with 95770's installed ... since I was not super picky about everything (aside from torque wrench installed plugs of course).

Filippo
 

Rob09msport

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I did have loose plugs when I had a misfire and then changed my coils I assumed i didnt need to change the coils and that the loose plugs cause misfire but now I'm just feeling stupid cause I dont get it. I would think misfire was lower pressure but I dont know I would have more bought that misfire causes washing and fuel and oil to hit the threads from inside and lube it up so spins. See how dumb that sounds though I'm gonna order my meth kit now so I can start a new series of adventures.
 

Itsbrokeagain

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I did have loose plugs when I had a misfire and then changed my coils I assumed i didnt need to change the coils and that the loose plugs cause misfire but now I'm just feeling stupid cause I dont get it. I would think misfire was lower pressure but I dont know I would have more bought that misfire causes washing and fuel and oil to hit the threads from inside and lube it up so spins. See how dumb that sounds though I'm gonna order my meth kit now so I can start a new series of adventures.


usually when we get a misfire the offending fuel injector is cut immediately. If my client had to drive the car somewhere to get it off the highway to erase the codes and reset, the EGT gauge will show a big difference in temp between each bank of cylinders (thanks @Chris@VargasTurboTech for supplying what might be the only set of GCs with EGT bungs in the manifolds), the proper running bank will show 750-800 F and the one with the dead cylinder will show 500. Not only that, Ill end up with AFR codes as one bank goes super lean due to one cylinder pumping air.

Unless your injector is stuck open....at that point, pray to God it dont hydrolock or wash the cylinder down LOL