[07denali]

Hey all new to this site just had a concern with my yukon. I have an 2007 denali with the 6.2 and i have noticed that when i turn it on there is gray smoke that is coming from the exhaust. Sometimes its enough to see from my rearview other times it's not. i have 27,460 miles on it, has anyone else had the same thanks

 

[likearock00]

Never heard of this happening before. Did you bring it to the dealership yet? I would not drive it until they get it figured out! When they fix it, let us know what the problem was.

Sorry that this problem has brought you to GMI, but welcome anyways. Put some pics of your truck up whenever you get the chance.

 

[FenwickHockey65]

That's odd. Oil burning off maybe?
Take it to the dealer and they'll check it out. Should still be under warranty.

 

[07denali]

im going to take it in first thing tommorow morning , it has had other problems like it would be hard to start dealer said it was a relay. Yes luckily its still under warranty. I hope it's nothing serious, i love my truck . i'll upload some pics soon thanks

 

[shadams]

Could be lots of things, including nothing. If it is light gray smoke, could be excessive carbon build up which is caused by poor fuel quality. Do you know you are supposed to use premium fuel, not many people know that. Also, sometimes a little romp on the pedal will keep it cleared out, esp if you are a very conservative driver. I would be very suprised if it were anything serious, but let us know what they say.

 

[07denali]

well that makes sense, i use mid grade fuel mostly mobil .. with prices here in california hitting 4.50 a gallon for premium i'll live with the smoke for a while .. i wil keep you updated thanks

 

[07denali]

2007 yukon denali smoke from exhaust at cold start up ??

i posted a thread on the tech form and thought i should post one here ,
i am having an issue with my 2007 yukon denali with the 6.2 engine. At cold start up i noticed a gray smoke coming from the exhaust , sometimes it's enough for me to see it from my rearview and if the wind is blowing it comes around to the front of the truck. Anyone else have this issue ? i was told it might be the grade of fuel i am using .. i use mobil mid-grade. i dont use premium since here in california i would be paying close to 5.00 a gallon .. any ideas thanks

 

[mbukukanyau]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

How old is the vehicle since you got it from the dealer new?

 

[07denali]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

bought the truck july of 06 has 27,450 miles on it

 

[mbukukanyau]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

bought the truck july of 06 has 27,450 miles on it

I thought it was new, just burning oil from the exhaust pipe

 

[2007CTS]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

take it to the dealer if it is burning oil. That could be a big problem starting!

 

[nailhead425]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

Is it actually burning oil or is it dense water vapor?

If you're not consuming oil, no worries.
You can check with a piece of old white bed sheet.
If it is oil, it will smell like oil and leave a film on the sheet.
It won't if it is just water vapor, it will just be wet.

Any film or excessive soot on the inside of the tail pipe?

Check the PCV valve too, it may be sticking.

 

[jkennedy293]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

If its oil it could be the valve seats are worn. Probably from heavy use like doing burnouts or other excessive high-RPM use.

 

[07denali]

a quick update . i took my truck in this morning the service guy asks me a few questions tells me that it is normal for the truck to blow out condensation and i agree, then he pops the hood open and takes my oil cap off looks underneath and says . " ohh i dont like this " looks like theres water inside the cap .. i'll let you know what happens

 

[SDRacing]

Re: 2007 yukon denali smoke from exhaust at cold start up ??

Way to early for valve stem seal replacement.

 

[07denali]

i baby my truck no burn outs or high RPM'S still waiting for the dealer to get back to me . wll keep you updated

 

[shadams]

a quick update . i took my truck in this morning the service guy asks me a few questions tells me that it is normal for the truck to blow out condensation and i agree, then he pops the hood open and takes my oil cap off looks underneath and says . " ohh i dont like this " looks like theres water inside the cap .. i'll let you know what happens

Famous last words....how's he going to explain what he said if the tech tells him he cant find anything wrong with it. I keep my mouth shut unless I am 100% sure of something so I dont open a can of worms.

Its not unusual to find moisture or condensation on the oil cap, after all, there is no water in the engine anywhere, only coolant. Moisture is a byproduct of combustion, thats why you always here if you do a lot of short trip driving you should change your oil more often, as the engine never has the chance to burn off the condensation in the crankcase which contributes to the creation of acids in the oil.

Now if there was orangeish brown gunk everywhere from coolant contamination, different story. Based on my experience with the 6.2L, I still will be suprised to hear there is something wrong with it. However, we replaced 1 entire engine in a 07 Denali after the valve got stuck in the head and it bent the pushrod all to hell. GM sent us an entire assembly and all they wanted back was the affected cylinder head. One of the techs scooped up the rest of the engine and plans on putting it his Jeep Wrangler....

Looking forward to hearing what they find......

 

[07denali]

well picked up my truck on friday, Shadams your right they found nothing wrong with the engine, i havent seen anymore smoke. but that doesnt mean it wont do it again .. they told me they did a compression test, a block test , and checked for any codes and found nothing ..

 

[FenwickHockey65]

It may have just been a random fluke. Cars do weird things from time to time.
I hope nothing else goes wrong with your truck. Post some pictures of it, I never get tired of seeing Denalis.