Ok so I bought my hummer about three months ago. It had 88k on it when I bought it and its a 2006 3.5. The day after I bought it I started it that morning and it puffed a little blue smoke. Well took it back to the dealer right away cause it had kinda a rough idle anyway and they said it wasnt smoking when I brought it in and it was fine. (also told me they ran a fuel injection flush and the rough idle was gone.) Well needless to say the rough idle didnt go away and they pissed me off with some other items so I just took it home, changed the plugs and the whole deal to try and get the idle to be better. So since no one has ever found the out how to fix the idle then I just moved on.) Well went to start the car today and the hummer was smoking again and threw a misfire cylinder 3. After about 30 seconds the smoke went away and I cleared the code and it hasnt come back on. Is this a early sign of the dreaded hummer ghost that costs a bunch of money to fix. Truck currently had 94k miles.

 

anyone>

 

The most common cause of blue exhaust smoke is oil leaking past engine seals and into the cylinders. I would have been persistent and had them fix it. I would say it's a pretty major issue and an important one to have addressed. Also when you clear codes they will stay off for a while but will come back on soon if the problem is not fixed. So that code will come back on. How much oil are you losing between oil changes? Or have you checked the oil level yet?

 

If you haven't already, search some of the MAF and Throttle Body cleaning threads for your rough idle.

From an old post of mine:
"The S/Ns affected is any 2006 H3 lower than 287591 .... the first one started with 100,001, your truck build date will be Nov. 06 or earlier. Not all have the problem, but some could. The head issue affected not only the I5, 4s and 6s were subject to the same issues. Call GM with your vin# and build date (from the sticker in the driver's door jam) and ask.

Just in case you're gonna say, wow they didn't even build that many 3s? The VINs are assigned at the same Shreveport plant building Colorados and Canyons. Their VIN sequence unit #s are mixed in and subject to the same TSB re: the head/valve issue.

The recall and extended warranty was for very early 2006s, those with the 3.5L L52 Motors built before March 31, 2006. That is not to say some 3.7L LLRs have never had a valve or head issue. All the Atlas motors built since 4/1/06 have the new hardened valve seats."

 

Concerning a surging or ruff idle.
Like Doc stated above, cleaning the MAF does help.
I have an 07 adventure with 5 speed trans and my idle was erratic and would drop very low and then recover. I just cleaned my MAF, last week, with the proper CRC - MAF cleaner and the idle was immediately stable. This won't fix all your problems, but it's a start
Good luck

 

I cleaned the tb and maf with no change. I did not take the tb completely off though. As for the truck im number s/n 109,445 produced in 06/05. 94,700 miles on the truck

 

talked to the dealer today and they totally acted like there is no apparent issue with the 3.5

 

A) Do some web surfing on the head issue and show at the dealer up armed with facts and evidence.

B) Take the TB all the way off to clean it properly.

 

I am brand new to the Forum. I decided to join after my 2007 H3 was diagnosed yesterday with bad head. Only 60,000 miles. I knew of the cylinder issues but I thought they were isolated to the 2006's only. Boy was I wrong. When the first service light came on, I already had the vision of $$$$$$ dancing in my head. As of right now, GM and I are not on the same page, so any advice on getting them to fix it, I would appreciate.

 

Our 07 had it too. GM repaired for free. Mine went at 75,000.