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07 5.3L 89k miles white cloud of smoke on start up

joshs1ofakindxj

Full Member
Joined
Jan 9, 2013
Messages
43
Hey everyone, I did some searching into this and found a lot of info about the older trucks, not so much on the newer trucks. I see now with the newer trucks the PCV is integrated into the driver side valve cover. Not sure if it is my problem.

I got the truck back in January, all was well. About a month ago I started the truck at work after my normal 8 hour day (20 mile drive to work one way) and a huge cloud of white smoke came out for a few seconds. It smelled kind of oily. I went around to the back of my truck to make sure something wasn't on fire! It was a big cloud of white smoke! Halfway home I noticed the same big white cloud come out for a few seconds. Since then I have never seen a white cloud occur while driving. It only occurs at about 25% of the start ups of the truck. The majority of the time there is nothing, but now and then there is that random concerning white cloud with an oily or burned plastic kind of smell.

I haven't noticed any loss of coolant, there is a small oil usage, but I haven't payed a lot of attention to it but I will try now to quantify it.

The truck runs great, never rough.

Should I be looking at replacing the PCV valve and valve cover? Is the AFM something I should consider disabling since I see it is mentioned a lot?

Thanks!
 
have you looked at your dipstick? ... make sure the oil is not goopy or whitish in color .... if so you have coolant leaking into your oil which usually mean a blown head gasket ....

1st thing I would do is get your oil changed and see what it looks like .... if it is black ... it is just dirty oil and something else is wrong ... if there is white stuff .... see above ....

I don't think it is your PCV valve ....

John
 
My 08 has been to the dealer twice for this issue, both times the valve cover and pcv were replaced.
Not sure if the revised pcv assembly can be replaced using the original valve cover.

I will see if I can find the work orders and post part numbers for you.

 
I changed the oil a few weeks ago and it looked good, and when I check the oil it's beautiful.

Those part numbers could be helpful. Thanks.
 
I too had the same problem, Mine was exactly as you describe. I would drive to work 32 miles it would sit all day for my 8 hours hit the remote start punching out and big puff of smoke, it would do it every other day? Granted I just purchase the truck and not sure the maintenance, I let out a quart of oil and replaced it with Marvel Mystery Oil    http://www.marvelmysteryoil.com/index.php/site/faq/  and ran it till the next oil change. I have not seen the white puff since?
Read the reviews or Google it
 
I will try any gimmick like marvel mystery oil at this point.

I did notice the smoke has a little darker or more bluish tint than I thought, still very light and white like overall.

I think I used a quart in 700 miles.
 
My '07 was having similar symptoms at 50k...I changed out my dino oil for mobile 1. The smoke has since gone away except minimal amounts here and there that could be condensation. I'm still using about a qt. every 1000 miles which I'm hoping is due to the AFM, I just bought a diablo sport intune to shut that off. Haven't had the chance to plug it in yet though.
 
joshs1ofakindxj said:
I will try any gimmick like marvel mystery oil at this point.

I did notice the smoke has a little darker or more bluish tint than I thought, still very light and white like overall.

I think I used a quart in 700 miles.

Turn Off AFM!....and pray it's not too late.
 
Do not use snake oil remedies, find and fix the problem, snake oil remedies in a can WILL cause more serious issue in the future. I have torn down many engines where these fixes in a can were used and it's never good.
 
Marvel Mystery Oil. What great nostalgia. And if it was good enough to not do anything good for for my '52 Chevy it oughta be good enough to not do anything good for my '08 Avy, wouldn't you think? 
 
AFM** Active Fuel Management.. It deactivates 4 cylinders when they are not needed, like when cruising on the highway. It has turned out to be more of a burdon than anything else... People have had lots of problems with it, losing compression, burning oil, and misfires. It's on 2007's and up...
 
MichInPa said:
OK, what is AMF ?

American Machine and Foundry aka "America's Manufacturer of Fun". Built bicycles. Once bought and ruined Harley. Best known today for bowling balls and equipment. Mercifully dead now, I believe. As AFM should be.
 
Hey guys, I'm stilling smoking on down the road, or just when I start I mean.

So the marvel mystery crap and sea foam did nothing, time to deactivate the AFM I guess.

What's my cheapest option? Range V8? A cheap tuner?

Should I keep running mobile 1 or is that not helping?
 
joshs1ofakindxj said:
Hey guys, I'm stilling smoking on down the road, or just when I start I mean.

So the marvel mystery crap and sea foam did nothing, time to deactivate the AFM I guess.

What's my cheapest option? Range V8? A cheap tuner?

Should I keep running mobile 1 or is that not helping?

Did you ever change the valve cover and internal PVC valve???
 
Scroll down to the 2nd post in this thread, Dealer replaced my valve cover twice for this issue, I think they got it right the second time!
The new valve cover has a revised PCV valve which is the main reason for the cloud of white smoke at startup.

It's a common problem on all 07 - early 09 GM 5.3, call the dealer parts dept, tell them the issue and get a price and part number on the revised valve cover and then shop around online for a decent price.
 
Ok so after a lot more google-Fu I think I'm going to attack this from multiple directions.

I found TSB 12-06-01-001B: http://powertrainintegration.com/Service/wp-content/uploads/2012/07/BULLETIN_12-06-01-001B.pdf

It says I need driver side valve cover 12570427 with the revised PCV baffle. I have more google-Fu to do but if anyone knows a cheap source for these help me out.

I'm due for an oil change soon so I will pick up some NGK3403 plugs (not a flex fuel) to see what the plugs show me is happening in the engine and do the upper cylinder cleaner with a 2.5 hour soak at the same time per TSB 10-06-01-008B: http://chevyavalanchefanclub.com/cafcna/index.php/topic,131291.0.html

At the same time I'm not sure how to go about tuning the ECM to shut off AFM. I see these plug and play things and I'm finding companies I can send my ECM to and they will reflash it, turning off AFM, ATM, and do a stock performance tune. Not sure which route is the best way to go. I have no experience changing fuel injection but like most things, I'm sure I can learn.
 
ltxi said:
American Machine and Foundry aka "America's Manufacturer of Fun". Built bicycles. Once bought and ruined Harley. Best known today for bowling balls and equipment. Mercifully dead now, I believe. As AFM should be.

An owner of an AMF era Harley called them America's Mal-Function.
 
SpynCycle said:
An owner of an AMF era Harley called them America's Mal-Function.

When I was in my late teens I saw an AMF badge on a buddy's Camaro.
I asked him at a red light what that meant. As the light turned green, he leaned out the window and floored it, yelling...
Adios Mother F*&%#r!!!!!!
 
^haha, adios MF'er...


Well my PCM is on it's way to Black Bear Performance to get the AFM turned off for $55.

I have a new valve cover to put on while the truck sits a week in the driveway without a brain. I bought a Dorman cover off of Amazon for less than $100. It doesn't have the redesigned square baffle but I could not find a cover for the 07-08 anywhere with that different baffle.

As soon as the PCM gets back I'll pull the plugs, soak the upper cylinders in cleaner for a few hours, blow it out, change the oil, and put in new plugs (NGK 3403).

Anything else I need to do to *try* and fix my smoking issue?

Oh and I ordered a 2" leveling kit so the truck doesn't look so low in the front. I don't think that will help the smoke issue much though!
 
Hey Josh, try to stay with the AC Delco Iridium plugs, most have found them to be the best plugs for the Avy. About the same price as NGK, even cheaper if Autozone etc has the rebate going on.
 
Check out the plugs I pulled:

IMG_2911_zpscf5053c0.jpg


IMG_2912_zps8088c83d.jpg


IMG_2913_zps4b28bd72.jpg


IMG_2914_zpsf6dbf507.jpg


IMG_2915_zps3f1865ce.jpg


IMG_2918_zps847f8476.jpg


IMG_2920_zps04b09513.jpg


 
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