Exhaust Smoke after changing spark plugs

[Matt Richards]

Hello All,

After searching around on the forums and reading up on some exhaust smoke threads, I wanted to put out a thread to get some help figuring this out.

So today I did some routine maint on my 06 Passat 2.0T (87K miles); Changed spark plugs (NGK BKR7EIX – gap .030), installed new coil packs, and changed the air filter. After starting up the car I now have smoke coming out of the exhaust. I noticed that the old plugs had black carbon deposits on the plug seal and while the engine cover was off I saw some oil spray that has me concerned. There is a small pool of oil to the right of the camshaft housing and oil spray around the intake. With all these signs I’m thinking this is definitely not good and could get very expensive and very time consuming to fix, very fast.

Since daylight savings hit and it’s a cloudy dull day, I didn’t get a great look at the smoke color. The smoke looked white and had a very sweet smell to it. I can usually hold my own when it comes to turning a wrench, but I have almost 0 experience diagnosing symptoms on cars, and even less ‘real’ ‘functional’ knowledge of automotive repair. I was recently thinking of taking a few night classes for automotive repair for this exact reason.

What exactly does burnt oil smell like at the exhaust? The exhaust tip does have black carbon deposits, nothing on the bumper. This only started after I changed the spark plugs and I did torque them to approx 30nm (18). I double checked the gap w/ a wire gap tool.

The car is brand new to me, I just bought 27 Sept and had a mechanic look over it, and got a thumbs up all good. The car has driven great, does have a CAT CODE stored for the after-market CAT installed, but no other issues. I have already driven over 2K miles since I bought it, and a road trip (1K round trip) with 0 issues. I’ve had some concerns over the CAT, in the last week/10 days, the MPG has dropped and there seems to be a slight dip in power.

Other notes about the car:
Automatic Trans
Aftermarket CAT (unknown age/brand/installer)

Dealer service record recommended replacing the transmission due to sticking in 3rd (have not experience any issue w/ 3rd/4th at all). The dealer, however, rates an F on every review site (including angies list).
Experience a ‘jolt’ when shifting from 1st to 2nd unless you allow a fast rev to 3k+

I’m open to any help/advice/input on this. It’s dark out now and I’ve put in 5 straight hours b4 light ran out trying to figure this out.

Thanks!

*Also while working on the car I did disconnect the negative term on the battery out of habit. Now the ESP is off and steering wheel light is on. Are there any other things effected by what I did? If so, what?

**I am attaching the best pics I could take of the engine (crappy phone) and of the old spark plugs.

[Edit]
I should have mentioned that I purchased an extended warranty that kicks in Nov 30th or at 88K miles, whichever is first. It’s a bumper to bumper warranty + emissions.

Spark Plugs:
[URL=”http://i.imgur.com/Vpv4q5h.jpg”]http://i.imgur.com/Vpv4q5h.jpg[/URL]
[URL=”http://i.imgur.com/rDVITZX.jpg”]http://i.imgur.com/rDVITZX.jpg[/URL]

Engine:
[URL=”http://i.imgur.com/cn9CYus.jpg”]http://i.imgur.com/cn9CYus.jpg[/URL]
[URL=”http://i.imgur.com/HzmdFHw.jpg”]http://i.imgur.com/HzmdFHw.jpg[/URL]

Topic

[Its me]

White smoke with sweet smell = Burning coolant
Black smoke = rich condition, fuel
Blue smoke = Oil

Get a look at the smoke color and check that oil issue when you have good light and keep us posted..

-Karl

[Matt Richards]

Is it possible this type of issue could be caused by over tightening the spark plugs? I’m trying to think of what could have happened since there were no issues before the maint.

Any chance it’s ethanol or water (condensation) being burnt?

[Matt Richards]

I just finished driving the car on a 75 mile ‘test drive’, combination city and highway. The sweet smell is gone, now the exhaust smells rich, very rich. Dropped by a friends house to get a second nose’s opinion. He agreed it’s not a sweet smell, it smells rich, ‘very rich’.

Good news is that my MPG went up quite a bit, used to get 16/17 in stop and go and now avg’d 21.9 banana: stop and go, and I was driving it pretty hard to draw out any symptoms or a CEL.

Does disconnecting the neg terminal on your battery effect the ECM? I’d imagine if it does it will correct the air/fuel mixture w/i a 100 miles or so. It is possible I ‘contaminated’ the MAF when changing the air filter. I will have to pull the connector and see if there is a difference in performance tomorrow when the sun comes up.

[Author]

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