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Blue Smoke While Idling

6225 Views 15 Replies 9 Participants Last post by  KB3MMX
I am a refrigeration tech and a member of an HVAC talk forum.

I started a thread over there with a question about my new van and was directed here - hope you can help.

My van had just over 100 miles on it when I picked it up last Friday and has been running great. Suddenly, at almost exactly 1000 miles, I started to notice bluish smoke coming from the tailpipe while idling.

A mechanic friend of mine says that in general blue smoke is "death smoke" on diesel engines but reiterated that he does not do much work on them himself.

Question: Is smoke in general and blue smoke in particular normal while idling for these engines (never had a diesel before) or should I park it until the dealer can get it in?
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Welcome to the site! Is your engine burning or losing oil? The engine should not really smoke at idle. I would take it back to the dealer to have them check it out. There might be an update out there to fix it.
No, its not losing oil. Checked it at both fill-ups and its right up there.

I guess I'll schedule an appointment with the dealer.....just didn't want to look like an ^ss for taking it in if there is nothing wrong with it.

Thanks for the input
is it just when the engine is cold or when up to temp?
The times I notice it the most is after I leave it idle for a while.

Example: I stopped at the wholesale house and left it run for about 20 minutes last Friday while picking up supplies. I left the wholesale house and for the first couple of stop/go lights the thing seemed to smoke the worst. I could actually smell the exhaust in the cab of the van.

Now today, I have been shutting it off at every stop and I don't notice it so much. Do you suppose the thing "loads up" while sitting idle for a while with the engine running?

I put in a call to the dealer today and they seemed to think it may due to the truck still breaking in but then told me I might want to get it looked at - they didn't seem overly concerned however.
...might be bad injectors
Id keep running it for another 2k or so and see how it goes, it will still be under warranty wont it?
Yes - it would still be under warranty.

My thought at this point is to monitor fuel mileage and oil level closely for the next thousand miles or so. If there is a noticeable decrease in either, I will have to get it in right away. If not, I'll just see how it goes for a while and make a decision at that point.

Thanks for the replies.
If you are having a new engine idle for long periods of time you are not doing it any good a diesel motor is not made to idle. especially when it is new the rings are not seated when you take it to the dealer he will scan the totals on the print out, Another thing check your oil and coolant in the morning before you start it on flat ground Check you auto trans at the end of the day when up to temp. PLAY SAFE!
Smoke

Had the same thing on mine. I work road construction and idle around the job 10-12 hrs a day. Noticed blue smoke while doing so and really smoked a lot when I hit the highway at cruise. The dealer checked it, said the fuel setting was rich causing unburned fuel to accumulate in the catalytic converter. When adding power to accelerate to highway speed the converter heated up and burned off the raw fuel causing a lot of smoke. The dealer upgraded the setting in the injection system and eliminated it completely. Hope this helps.
my truck has 17000 miles on it and if i let it sit for any period of time it wil start to smoke been doing it since i bought it still running stron g
My 07'does it too if it idles a long time more than 5 minutes). I'm pretty sure that the EGT's have gotten soo cool that you are seeing unburnt fuel out the pipe. Kinda like a tractor trailer that sits and idles a long time, it gets cool and starts smoking.
mine was doing it again yesterday while i was at the dealer and he said that it was just unburned fuel because of no load on the motor
mine was doing it again yesterday while i was at the dealer and he said that it was just unburned fuel because of no load on the motor

Exactly....!:drink

Low EGT's from low load, leaving unburnt fuel...


I would imagne that the LBZ's are somewhat worse at no load extended idle smoking than the previous motors due to the lower compression ratio ....:gearjamin
Have a similar issue---at about 4000 miles my lbz seemed to loose some power--I noticed it first when passing---it didn't put you back in the seat as it used to---took it to the dealer and he said nothing was wrong--then noticed the smoke when idleing and also notice a kind of sharp burnt smell not a "sweet" diesel smell in the exhaust. finally it seemed that the mileage dropped a couple of mpg. Other than that, it runs good but just doesn't seem to have the zip it did have i now have 17000 miles and get about 11-16 mpg city/highway. Dealer says no codes, nothing wrong?? is my catalytic converter plugged up? would a "chip" help?
Have a similar issue---at about 4000 miles my lbz seemed to loose some power--I noticed it first when passing---it didn't put you back in the seat as it used to---took it to the dealer and he said nothing was wrong--then noticed the smoke when idleing and also notice a kind of sharp burnt smell not a "sweet" diesel smell in the exhaust. finally it seemed that the mileage dropped a couple of mpg. Other than that, it runs good but just doesn't seem to have the zip it did have i now have 17000 miles and get about 11-16 mpg city/highway. Dealer says no codes, nothing wrong?? is my catalytic converter plugged up? would a "chip" help?
Maybe something is hangin up with your EGR?
That mileage seems pretty low as we usally get between 14-16City and 18-20 Hwy with our 07'. I have seen as low as 15Mpg highway pulling the trailer @ around 75-85Mph in the mountains.



Maybe try taking the truck out and flogging it to "clean it out"....? Then see if things improve......these trucks seem to like to be ran with a good load once and a while or they load up a little.:Bullwhip:
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