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white smoke from exhaust and horrible gas mileage

16K views 33 replies 13 participants last post by  WDC_JGC_Overland 
#1 · (Edited)
Ugh. So my new Overland (5.7 hemi with 500 miles) is already having problems. Twice on start up it coughed a big white cloud of smoke out the exhaust. It was a cold start and my car was on an incline -- another thread indicated that parking on an include tends to provoke the issue.

I don't know if it's related but I'm also getting horrible gas mileage. On my first tank I averaged 10 mpg and on this second tank, it looks like I'll do worse at about about 8 mpg. Granted I have a lot of stop lights around my neighborhood and some hills, but boy is this bad fuel economy. I don't drive with a lead foot and am very conscious about keeping the RPM's low -- always aiming for ECO mode. I have an appointment with the dealer this Wednesday but from reading other threads it appears most have taken theirs to the dealer to no avail. Pretty frustrating...looks like I'll be ponying up for the unlimited extending warranty.
 
#2 ·
What grade of fuel are you using? I routinely get 15-17 on country roads/town and easily 19-20 on the highway. Are you relying on the EVIC for your MPG or are you hand calculating it? The white smoke thing appears to be a hit or miss problem. I personally don't have that issue and I park nose up most times and remote start to make sure I don't see a bunch of smoke as I walk up to the vehicle.
 
#4 ·
Hmm, I normally run Shell 89 but I can't see that making that much of a difference. I would definitely check with the dealership about your fuel consumption. As far as the smoke goes, I don't think there is a definitive 'fix' for it and unless you see heavy oil consumption between changes I wouldn't worry too much about that. I guess try a couple more tanks of gas and see if your mileage comes out any different. I hand calulate mine and it's normaly 17.XXX depending on how much highway I drive.
 
#5 ·
White smoke is generally water vapor. If it coughed it out, that might be an issue. It's not uncommon for condensation to form in the exhaust system as things cool overnight after a humid day. At certain times of year I get white smoke for the first mile or two. This is with my current MDX, my previous Jeep, and my TrailBlazers before that.
 
#6 ·
That's reassuring and I hope it is benign. The first time it happened I figured it was probably water vapor but so I didn't pay too much attention. But the second time it happened I felt like it was too much substance to be vapor. It practically enveloped half of the car. I didn't smell anything strong though...
 
#7 ·
Its not water vapor. My smokes at startup year round. It only happens when on a slight incline and it envelopes the entire car. Its a big cloud of bluish white smoke that only lasts for about 10 seconds. Water vapor will lasts longer. Jeep knows about this and its a bad design of the oil pan. The sump is reversed so the deep part of the pan is forward vs rearward. On an incline the oil pools in the rear of the pan and oil seeps past the rings so at startup that oil burns off causing the smoke. There was talk of a fix but so far nothing.
 
#12 ·
Dropped her off at the dealer today. We'll see what they say. I'm not overly optimistic based on what the guy at the service desk said this morning. Basically, without seeing the car, said it probably is due to something that happens in transit...something about a film that builds up. It made absolutely no sense and I told him it's a known, documented issue that a simple Google search would reveal.

I'll let you know that this dealer says.
 
#13 ·
Bull pucky, it's not a film that builds up in transit. When I took mine in for the same issue last week I made sure to have a conversation with the service manager about it. I offered video of my vehicle proofing out the "oil" smoke, and suggested he research it online, which he did. He also contacted Chrysler for guidance. Chrysler IS aware of this problem and had the dealer replace the PVC valve, which is their standard plan of attack for this issue at this point. Changing the PVC valve does not and did not correct the smoking but we didn't really expect it to. The service manager told me that it may be caused by a faulty part or an error in design (most likely I think) and that Chrysler engineers are working on a fix for this but it may be awhile. There are many threads about the issue on this forum and the other jeep forum, I suggest reading them all. And most of all, GOOD LUCK :) AND if your dealer pulls off some kind of miracle and manages to fix it be sure to let the rest of us know what they did!
 
#15 ·
Not surprised, they didn't find anything wrong. Couldn't replicate the problem and it didn't throw any CEL errors so apparently there's no issue. Whatever.

Oh yeah and the funny part is, they took the car on a 20 mile test drive (not sure how I feel about that) to ascertain the MPG issue. The guy tells me that it clocked an average 18 MPG (all highway mind you). However, when I jumped into the vehicle I saw the EVIC numbers and it read 12 miles for that particular run. Underwhelmed by this dealer.
 
#16 ·
My V6 gets 12 MPG (I have 5,000 miles on my WK2) during my "regular" driving cycle in NYC (infrequent short trips that often end soon after engine warmed up). On highway I get 23-24 MPG, during longer drives in the city - 15-16 MPG. So 10 MPG with HEMI doesn't seem abnormal if the driving cycle is mostly short city trips, and hills sure aren't helping.

Now if you say you sometimes get 8 MPG this does seem too low even for HEMI. On my old '98 ZJ with 5.2L V8 I never got less than 10 MPG in my city cycle.
 
#17 ·
For my third tank of gas I filled up at Shell (89 octane). The first two tanks were with Mobile. I've only gone through about a 1/4 tank so far, but it appears my MGP has improved a lot. Too early to call it a success, and I'm somewhat doubtful that a different gas type can make that dramatic of a difference, but I'm optimistic.

Anyone else have success with certain brands of gas?
 
#18 ·
My 2014 JGC Hemi Limited does the same thing; belches bluish smoke when starting up even on a very slight incline. Dealer says STAR is telling them to keep overnight on incline, then drop the pan and remove half of the mechanism to see if they can solve the problem. Guess I will do it because the smoke has to be a problem brewing. Mileage is 18-20, so that hasn't been affected so far.
 
#19 ·
My 2014 JGC Hemi Limited does the same thing; belches bluish smoke when starting up even on a very slight incline. Dealer says STAR is telling them to keep overnight on incline, then drop the pan and remove half of the mechanism to see if they can solve the problem. Guess I will do it because the smoke has to be a problem brewing. Mileage is 18-20, so that hasn't been affected so far.
RR,Let us know how you make out....mine spits out a little smoke on a slight incline also....good luck
 
#20 ·
I am working with my dealer as well. I installed a catch can a few weeks back hoping for a fix. It has not smoked since then, but I am still waiting. Dealer and Chrysler has not clue on how to fix this issue yet.
Some people have the CC and it still smokes.
Have you opened a STAR case with Chrysler yet? if not, do. I am sure you will get the same thing I got, "No we have not heard of that issue before". But if enough people open cases maybe someone up there will take notice.
 
#21 ·
2012 JGC_Overland
Under 10,000 miles

Seven (7) visits to the dealer about white smoke from the tailpipe. It is not happening at initial start it is happening LONG after the vehicle has been running and is at standard operating temprature (at or just below mid gauge). Sixth incident happened while I was volunteering at the Avon Walk and delivering supplies. Had the back open while unloading water at an aid station and CLOUDS of WHITE SMOKE came pouring out of the tailpipes. This had happened before so I wasnt freaked out but everyone else was screaming for someone to shut off the car cause it was on FIRE!!... I am stating all of this so folks understand the quantity and how startling the smoke was in this situation. So to be clear what I am experiencing with my car IS NOT a condensation issue... the smoke has a odor but it is tough to place. It is WHITE not blue.. not black... not orange with pink poka dots... it is WHITE and comes out in small or large quantities and does not replicate in any discernable fashion. On my 7th visit to the dealer I handed them the keys and said I wasnt taking the car back till they had found something and done some sort of corrective action. On this visit they took the heads off and resurfaced them to ensure they had perfectly level surfaces even though they measured in tolerance. They replaced all the top end gaskets and gave me back my SUV. Roughly two weeks have passed and we have had our 8th incident that I have been able to document on video. I am in the process of seeking replacement with Chrysler/Jeep and I will let you all know how it pans out. If I am happy with the process and terms they put forward then I will work with them... otherwise I guess I will have to lawyer up and take this to task. $50K+ SUV shouldnt be doing this and this is an issue that is happening to frequently to other owners from what I have been reading for the corporate stance to be isolated instances. BTW I am pressing for a new replacement and not seeking some sort of monetary settlement. We love our Jeep products we are just having a bad experience with this one... I hope
 
#23 ·
No fluid levels show any differences that I have found. I have been checking antifreeze, oil, and transmission fluid levels this entire time trying to figure this out.

Honestly if it was any significant amount of water it would cause the car to run really rough or possibly even cause it to shut off. So I am wondering if it is a very fine crack in the block along one of the cooling tube/shafts that when conditions are just right (pressure, temperature, cooling/expansion of metal) that it allows a very small amount of fluid to pass and this is creating white smoke... this is all hypothetical but it seems more likely then the myriad of BS I have been fed to date.
 
#24 ·
Small amounts of white smoke is normal condensation in the exhaust. The light blue smoke is from oil in the intake/cylinders. Not sure exactly it is. The blue smoke normally a lot and after about 3 seconds start up. At least with mine it is.
 
#25 · (Edited)
Just a thought but I would loosely hold a gallon freezer bag (possibly with an outher bag of ice) over the tailpipe when doing it and have the condensate analyzed. Then you would know where it is coming from.

BTW I have seen a ruptured vaccuum modulator do something similar. Did you check the level of the automatic transmission fluid ?

ps blue smoke on startup (and sometimes on accelleration) is often worn valve guides. If it were a six, I'd check for misfires.
 
#26 ·
Just as a matter of point here white smoke from condensation would be expected at initial start up not long after vehicle was brought up to temp. Blue smoke should not be expected in the exhaust from a new motor... ever... if you are being told that then they are avoiding the issue. Blue smoke is oil getting past rings, valves or gaskets and will only worsen with time.
 
#28 ·
Get you a catch can and that will fix the issue. It did for me at least. Chrysler has no clue or desire to fix this.
 
#30 ·
I got mine from Billet Technologies. They give you great instructions. Takes about 20 min to install. I empty it out before a oil change. Normally good for at least 3000 miles.
 
#32 ·
HtownBB--

Thank you SO MUCH for the information! I see now that the white smoke can indeed come from the passage of oil/petroleum condensate reintroduced to the intake system; as presently designed; further, that this phenomenon is characteristic of all Hemi engines throughout the Chrysler product line. So much so in fact that a product line has been created by (at least) two aftermarket manufacturers (Billet Technology and Moroso) to manage this Chrysler design error.

Billet says that they are "Mopar Performance Parts Approved": not sure however whether installation of the product might void the vehicle warranty.

Final continuing question is why the "white smoke" only occurs, on some cars, only when idling and facing uphill (~10deg incline).

In any case, guess I can at least put the fire extinguisher away and approach the problem a step at a time.
 
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