Running lean or Rich
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Joined: Dec 2014
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From: Indianapolis
2004 E55.98 SS Camaro.Jetta TDI. Expedition
How many miles on them. The color looks good for mixture. There are some deposits that can be caused by fuel additives or a little oil. They don't spell trouble from what I have seen.
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From: Canada
07 E63 + 07 CLK63CAB
The red cat is unburnt fuel being admitted into the catalytic converter, this fuel then causes the cat to glow. U must have been getting some misfire codes-Yes?
Rich condition or by the look of those plugs they were used up. The deposits are poor fuel quality or some oil deposit ash. This car needs new plugs and a good long highway drive.
Good Luck
Rich condition or by the look of those plugs they were used up. The deposits are poor fuel quality or some oil deposit ash. This car needs new plugs and a good long highway drive.
Good Luck
Thread Starter
Super Member
Joined: Jan 2008
Posts: 626
Likes: 8
From: UK
E55K AMG
thanks, about 20-25k miles, its been running rich.....So will see what the difference is now that they are changed to one step colder plugs
Last edited by £ C43 £ AMG £; Oct 22, 2015 at 12:58 PM.
Thread Starter
Super Member
Joined: Jan 2008
Posts: 626
Likes: 8
From: UK
E55K AMG
The red cat is unburnt fuel being admitted into the catalytic converter, this fuel then causes the cat to glow. U must have been getting some misfire codes-Yes?
Rich condition or by the look of those plugs they were used up. The deposits are poor fuel quality or some oil deposit ash. This car needs new plugs and a good long highway drive.
Good Luck
Rich condition or by the look of those plugs they were used up. The deposits are poor fuel quality or some oil deposit ash. This car needs new plugs and a good long highway drive.
Good Luck
thanks, that's what the manifolds look like on first start up when you have a vacum air leak after the throttle body.......bad to drive like this
Last edited by £ C43 £ AMG £; Oct 22, 2015 at 12:59 PM.
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From: San Diego
E55
Not lean thats for sure. You want to see a nice toasty brown on the spark plugs. But, all that gunk No. Looks like carbon build up, burnt oil and reside from not going WOT.
Critter said it best. I think you should take his advise. Put new plugs and go for nice long drive and go WOT and clear the motor out of carbon buildup.
Critter said it best. I think you should take his advise. Put new plugs and go for nice long drive and go WOT and clear the motor out of carbon buildup.
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Thread Starter
Super Member
Joined: Jan 2008
Posts: 626
Likes: 8
From: UK
E55K AMG
Not lean thats for sure. You want to see a nice toasty brown on the spark plugs. But, all that gunk No. Looks like carbon build up, burnt oil and reside from not going WOT.
Critter said it best. I think you should take his advise. Put new plugs and go for nice long drive and go WOT and clear the motor out of carbon buildup.
Critter said it best. I think you should take his advise. Put new plugs and go for nice long drive and go WOT and clear the motor out of carbon buildup.
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MBWorld Fanatic!
Joined: Jul 2012
Posts: 1,556
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From: Canada
07 E63 + 07 CLK63CAB
As stated the look of the plugs shows good color but the deposits are oil residual or poor grade fuel. I definitely would not put colder range plugs in this car but would look at oil consumption or PCV valve issue or just normal slow city operation.
Running rich would have shown a darker color on the plugs and as for oil if your compression is good there is enough gas vapor in the chamber to burn the oil to an ash. Lean condition the plugs would be whiter, check on the net for reading spark plug color.
You may see a puff of blue smoke on first start or when using the engine as a brake on a steep hill, leave it in first or second gear let the revs build to around 3500-4000 using the brake to hold back further revs then step on the gas quickly for a second, this will produce a blue cloud or blue tinge if valve guides are bad or you are sucking oil mist into the manifold/supercharger.
Colder plugs are not recommended, even 1 step higher if this is the normal driving you do or possibly you just bought the car and the previous owner drove it "softly".
Just Sayin,
Good Luck
Running rich would have shown a darker color on the plugs and as for oil if your compression is good there is enough gas vapor in the chamber to burn the oil to an ash. Lean condition the plugs would be whiter, check on the net for reading spark plug color.
You may see a puff of blue smoke on first start or when using the engine as a brake on a steep hill, leave it in first or second gear let the revs build to around 3500-4000 using the brake to hold back further revs then step on the gas quickly for a second, this will produce a blue cloud or blue tinge if valve guides are bad or you are sucking oil mist into the manifold/supercharger.
Colder plugs are not recommended, even 1 step higher if this is the normal driving you do or possibly you just bought the car and the previous owner drove it "softly".
Just Sayin,
Good Luck
