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 What does this mean when my spark plugs look like this?
FALARAK  [Team Member]
3/4/2011 6:09:28 PM
Check engine light came on today. Idling rough and sounding like not hitting on all cylinders. Took the 1999 Dodge RAM 5.9L 2500 by Auto Zone to pull the OBDII codes. Cyl #8 Misfire. So I bought a set of plugs and headed home.

Truck had a set of Bosch Platinum dual electrode plugs from the previous owner. Cylinders 7 and 8 looked bad! Especially #8. All the rest looked totally normal.

#8 was caked with oil, and completely filled in - no gap of any kind left, and the junk inside the plug is like cement... like I cant even pick it out its so hardened.
#7 is not as bad, but a LOT of deposits built up on this thing.

Is this a sign of a serious engine issue... or just this engine not liking the plugs... or?

Cyl #8:



Cyl #7:
ElectricSheep556  [Team Member]
3/4/2011 6:10:11 PM
Holy fuck, that's bad...
Taffy223  [Team Member]
3/4/2011 6:11:28 PM
It'll buff out...no worries
v-twintech  [Member]
3/4/2011 6:12:27 PM
You have an oil control problem in that cylinder.
FALARAK  [Team Member]
3/4/2011 6:12:43 PM
Adding - I hate Bosch Platinum plugs... I have found way too many engines that dont like them. I installed Autolite standard copper plugs back in this. It ran like a top as soon as they were replaced.

I am worried #8 might be going to just foul up again soon.

And I am curious - what are all those deposits on #7?
Danman  [Member]
3/4/2011 6:12:48 PM
I'd be slightly concerned. Thats pretty nasty
Maybe you should do a tune up and check the state of your engine now and then
Cowboy1967  [Team Member]
3/4/2011 6:14:16 PM
Do you seem to use coolant? I think your head gasket might be leaking
chibajoe  [Member]
3/4/2011 6:14:26 PM
Originally Posted By FALARAK:
Check engine light came on today. Idling rough and sounding like not hitting on all cylinders. Took the 1999 Dodge RAM 5.9L 2500 by Auto Zone to pull the OBDII codes. Cyl #8 Misfire. So I bought a set of plugs and headed home.

Truck had a set of Bosch Platinum dual electrode plugs from the previous owner. Cylinders 7 and 8 looked bad! Especially #8. All the rest looked totally normal.

#8 was caked with oil, and completely filled in - no gap of any kind left, and the junk inside the plug is like cement... like I cant even pick it out its so hardened.
#7 is not as bad, but a LOT of deposits built up on this thing.

Is this a sign of a serious engine issue... or just this engine not liking the plugs... or?

Cyl #8:
http://kevinholman.com/host/spk_8.jpg

Oil fouling, detonation


Cyl #7:
http://kevinholman.com/host/spk_7.jpg

Water deposits, possible oil fouling


Looks like you might have a blown head gasket.
FALARAK  [Team Member]
3/4/2011 6:15:10 PM

Originally Posted By v-twintech:
You have an oil control problem in that cylinder.


As in - busted/worn ring, or leaky valve stem seal?

Every once in a while, the first startup of the day - I will blow a substantial amount of blue smoke out the tailpipe, for about 3 seconds after starting - then its gone. This doesnt happen every time.

The truck does use oil. Only 99,000 miles on the engine though. Previous owner was a airline pilot - all records, always used mobil 1 synthetic (I changed it back over to dino oil when I got it, and have been using that ever since)
ROB_B  [Member]
3/4/2011 6:15:30 PM
Originally Posted By FALARAK:
Adding - I hate Bosch Platinum plugs... I have found way too many engines that dont like them. I installed Autolite standard copper plugs back in this. It ran like a top as soon as they were replaced.

I am worried #8 might be going to just foul up again soon.

And I am curious - what are all those deposits on #7?


It may be fine now but you have other issues. Not a spark plug issue.
WGPKlaus  [Team Member]
3/4/2011 6:15:38 PM
Check your headlight fluid resevoir, looks like the manifold gasket is bad, allowing overflow headlight fluid into the cylinder(s). If that's ruled out, try checking your flux capacitor, it's possible that the fuel rods had started to degenerate, thus not allowing optimal spark?

Godspeed.
Andrewh  [Member]
3/4/2011 6:16:14 PM
5.9 magnum motors with the beer barrel intake has a seperate plate at the bottom.
that gasket is known to go bad and allow the intake to suck in oil.
bet you have been using a little oil between changes.

pull the intake and reseal. should go away.
several kits that put a stronger plate on the bottom so it is less likely to warp, or you can go with the m1 intake that usually runs around 400 bucks used that doesn't have the plate.
Justa_TXguy  [Team Member]
3/4/2011 6:16:22 PM
I had a 96 5.9L with Bosch Platinums in it for over 100k miles and they never, ever looked like #7 or #8.

To be honest, I'm not sure what that means. I'd probably change the plugs (you already did) and also put on a new cap and rotor and plug wires.

FALARAK  [Team Member]
3/4/2011 6:16:34 PM

Originally Posted By WGPKlaus:
Check your headlight fluid resevoir, looks like the manifold gasket is bad, allowing overflow headlight fluid into the cylinder(s). If that's ruled out, try checking your flux capacitor, it's possible that the fuel rods had started to degenerate, thus not allowing optimal spark?

Godspeed.


Is that before or after I top up the blinker fluid?
SV650Squid  [Team Member]
3/4/2011 6:16:40 PM
probably ash on the 2nd one from burning oil.

does your truck smoke?
BeRzErKaS  [Member]
3/4/2011 6:17:24 PM
The piston ring in cylinder 8 is shot. Oil is passing into the cylinder and fouling the plug.

Run a compression test on all cyclinders and report back.
Badass03  [Member]
3/4/2011 6:18:15 PM
you should run a compression check on all cylinders
Banditman  [Team Member]
3/4/2011 6:18:34 PM
Do a compression or cylinder leak down test!
NoloContendere  [Team Member]
3/4/2011 6:18:42 PM
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp


check this out. it shows you pictures and tells you what is wrong with your engine.

eta: yours is fucked. sorry
imdeeds  [Member]
3/4/2011 6:18:46 PM
#7 looks like water(head gasket) #8 is oil maybe valve seal.
schizrade  [Team Member]
3/4/2011 6:18:53 PM
OP, PM Toiyabe66.

He can probably point you in the right direction on this one.
Badass03  [Member]
3/4/2011 6:19:36 PM
Originally Posted By Badass03:
you should run a compression check on all cylinders


ETA: Damn, need to refresh before responding.

oh well
FALARAK  [Team Member]
3/4/2011 6:19:41 PM

Originally Posted By Andrewh:
5.9 magnum motors with the beer barrel intake has a seperate plate at the bottom.
that gasket is known to go bad and allow the intake to suck in oil.
bet you have been using a little oil between changes.

pull the intake and reseal. should go away.
several kits that put a stronger plate on the bottom so it is less likely to warp, or you can go with the m1 intake that usually runs around 400 bucks used that doesn't have the plate.

Man that sounds good! Because it does use oil... but the engine has always been well cared for with synthetic oil. I have the factory service manual and will read up on this.

K2QB3  [Member]
3/4/2011 6:21:36 PM
Yeah I think that's a head gasket or possibly a manifold gasket, is there any white stuff under the oil cap?

#8 looks like has struck oil, #7 could be coolant but I've seen plugs look like that from extreme lean condition too, could be from an atmosphere leak either at the head or the manifold.
nightdh  [Team Member]
3/4/2011 6:23:43 PM

Originally Posted By Andrewh:
5.9 magnum motors with the beer barrel intake has a seperate plate at the bottom.
that gasket is known to go bad and allow the intake to suck in oil.
bet you have been using a little oil between changes.

pull the intake and reseal. should go away.
several kits that put a stronger plate on the bottom so it is less likely to warp, or you can go with the m1 intake that usually runs around 400 bucks used that doesn't have the plate.

This
LazarusLong  [Member]
3/4/2011 6:24:52 PM

Originally Posted By imdeeds:
#7 looks like water(head gasket) #8 is oil maybe valve seal.

From what I remember usually coolant or water into a cylinder will burn the carbon out because of the higher combustion temp.
speedfreak955  [Member]
3/4/2011 6:25:17 PM
Originally Posted By K2QB3:
Yeah I think that's a head gasket or possibly a manifold gasket, is there any white stuff under the oil cap?

#8 looks like has struck oil, #7 could be coolant but I've seen plugs look like that from extreme lean condition too, could be from an atmosphere leak either at the head or the manifold.

My deduction as well.

Toiyabe66  [Life Member]
3/4/2011 6:25:40 PM
Ok.

1) Bosch Platinum plugs are the devil. We will not sell them. Especially the +2 and +4.
2) Those engines have notorious problems with intake manifold gaskets. I guarantee yours need to be replaced.

WinstonSmith  [Team Member]
3/4/2011 6:27:57 PM
Originally Posted By FALARAK:
Adding - I hate Bosch Platinum plugs... I have found way too many engines that dont like them. I installed Autolite standard copper plugs back in this. It ran like a top as soon as they were replaced.

I am worried #8 might be going to just foul up again soon.

And I am curious - what are all those deposits on #7?


Im not a mechanic. I fix computers. I know a really good mechanic though. My car was pinging something fierce. Asked him to look. Before we went down, he sez "wait a sec, I betcha we find Bosch platinum plugs."

Sure as shit dude.

My civic calls for NGKs in the manual, and the issue stopped with the Bosch plugs swapped for them.

They didn't look like THAT though.
Andrewh  [Member]
3/4/2011 6:28:33 PM
it is not a maintence issue.
the plate is just poor design. it is very thin and has a paper thin gasket. it is a known issue with magnum intakes, and there are at least 2 different companies that make kits to repair it like hughes and even mopar sells one.

eventually it just warps or gives up the ghost.
you can pull the throttle body to check. shine a flash light inside and see how much oil is in there already.
novaDAK  [Team Member]
3/4/2011 6:30:18 PM
Get some Autolite 3923's. Recommended and used by a TON of dodge enthusiasts in 5.2/5.9 engines. I use them in mine. Cheap. And I found them at Wal-Mart.


Originally Posted By Andrewh:
it is not a maintence issue.
the plate is just poor design. it is very thin and has a paper thin gasket. it is a known issue with magnum intakes, and there are at least 2 different companies that make kits to repair it like hughes and even mopar sells one.

eventually it just warps or gives up the ghost.
you can pull the throttle body to check. shine a flash light inside and see how much oil is in there already.

Yep the plenum pan gasket is a known issue with the magnum 5.2/5.9. Besides the design, it's also the materials. Heads are cast iron, intake manifold is aluminum, and the plenum pan is stamped steel. All three of these materials expand and contract at different rates when the engine warms and cools. Hughes Engines's fix is a plenum pan made from aluminum so it expands at the same rate as the intake manifold. I'd assume that mopar's fix is similar.
Palm  [Team Member]
3/4/2011 6:32:13 PM
Do yourself a favor and only use the exact same plugs the manufacture uses. There are way to many variations and tight tolerances to be using a house brand or some sort of fancy new stile. There are a lot of engines out there that are not tolerant to variations in the spark plugs.
Dumpster_Baby  [Team Member]
3/4/2011 6:33:01 PM
Confession time.

I have a 1991 Suzuki Sidekick I bought in late 1990. The spark plugs have never been out of it because it runs fine. Now I'm afraid to try to remove them because it would probably strip the threads out of the aluminum cylinder head.

Anyone else drive on the same plugs for 20 years?


Vicinity  [Team Member]
3/4/2011 6:33:25 PM
Originally Posted By ElectricSheep556:
Holy fuck, that's bad...


That's exactly what I just said out loud.
stanprophet09  [Team Member]
3/4/2011 6:35:37 PM
Originally Posted By FALARAK:
Adding - I hate Bosch Platinum plugs... I have found way too many engines that dont like them. I installed Autolite standard copper plugs back in this. It ran like a top as soon as they were replaced.

I am worried #8 might be going to just foul up again soon.

And I am curious - what are all those deposits on #7?


That is normally coolant fouling!

I would run some champion plugs in it for a month and pull them to check , or you can run a compression and leak down test.
stanprophet09  [Team Member]
3/4/2011 6:37:44 PM
Originally Posted By Andrewh:
5.9 magnum motors with the beer barrel intake has a seperate plate at the bottom.
that gasket is known to go bad and allow the intake to suck in oil.
bet you have been using a little oil between changes.

pull the intake and reseal. should go away.
several kits that put a stronger plate on the bottom so it is less likely to warp, or you can go with the m1 intake that usually runs around 400 bucks used that doesn't have the plate.


This is good info, i forgot about the plate!
Jame_Retief  [Team Member]
3/4/2011 6:39:14 PM

Originally Posted By FALARAK:

Originally Posted By Andrewh:
5.9 magnum motors with the beer barrel intake has a seperate plate at the bottom.
that gasket is known to go bad and allow the intake to suck in oil.
bet you have been using a little oil between changes.

pull the intake and reseal. should go away.
several kits that put a stronger plate on the bottom so it is less likely to warp, or you can go with the m1 intake that usually runs around 400 bucks used that doesn't have the plate.

Man that sounds good! Because it does use oil... but the engine has always been well cared for with synthetic oil. I have the factory service manual and will read up on this.


Previous owner was a airline pilot - all records, always used mobil 1 synthetic (I changed it back over to dino oil when I got it, and have been using that ever since)

So which is it? Have you gone back to dino oil or are you using synthetic?

IANAE, but I recall hearing that once you go synthetic you cannot go back but never heard an explanation as to why. BRB, let me google and see what I come up with.


ETA: On brief search there is nothing definitive, but one source said that going to synthetic can open you up to some leakage due to deposits coming loose with the change in oil types. Nothing about going the other direction.
FALARAK  [Team Member]
3/4/2011 6:58:56 PM
Thank you arfcom.

I dont know why I never saw this discussed before.

I am almost 100% certain i have a blown out plenum gasket which is causing the engine to suck oil into the intake... seems to be a VERY common issue on these engines.

http://www.hughesengines.com/Index/products.php?partid=26190

http://www.youtube.com/watch?v=SLWFbU7ivVo

My symptoms are identical. 2+ years of living with this pinging, and burning super unleaded, and adding a quart of oil every two weeks. I just thought it was worn.... or a bad valve seal.
Mousegun  [Member]
3/4/2011 7:02:27 PM
With smoke on start up, don't discount valve seals being worn.
FALARAK  [Team Member]
3/4/2011 7:24:55 PM

Originally Posted By Mousegun:
With smoke on start up, don't discount valve seals being worn.

Smoke on startup can also be because I park on an incline (driveway) - which will drain the residual oil off my plenum pan and into my rearmost cylinder..... which happens to be the one that oil fouled.

But I will inspect for a valve seal when I have it all apart.


craigsar15  [Member]
3/4/2011 7:46:34 PM
While you have the plenum off, inspect all wiring harness and sensors that are underneith. Old brittle wires and plugs can fail when moved. If the knock sensor is under the plenum I would replace it. It's cheap insurance for further problems. Replace all PCV valves, grommets, hoses, and other parts with oem parts.

It would also be a good time to do the valve cover gaskets and clean out the PCV oil separators and channels.

I would run synthetic oil and factory spark plugs. Synthetic oil has a higher flash point and leaves less deposits. Don't worry about synthetic in an old engine. It has additives to lube the seals and keep the gaskets wet. Run a blend if you are scared, and switch to full synthetic after several oil changes.

My 2 cents.

By the way. Take those worthless Bosch Platinums and smash them with a hammer. If you want to run platinum plugs get some good NGK or ND dual platinum plugs. I would just run the oems and replace them often or rotate them cylinder to cylinder when crusty.