I have a 2007 H3 with 65,000 miles. I have had it for two months now. I was running about 85-90 yesterday for a few miles, and when I slowed down, I got a traction control failure message. The roads were perfectly dry. I made it home with no issues. When I went to leave about 10 minutes later, the truck started just fine, idled normally for about 5 seconds, bogged down for 10-15 seconds, then died. At a higher RPM, it's the same story. Bogs then dies. I do not have a check engine light. I tried the "miracle fix" this morning, (cleaned out throttle body and MAF sensor) and while the throttle body was quite dirty, the issue persisted. I have babied this truck since I bought it. Yesterday was the fastest I've taken it, and I wasn't even pushing it hard. Any ideas/theories would be greatly appreciated...

 

dirty air filter maybe? leak in the hose running from air box to the trottle body? maybe check the coil packs. i had an issue with one of the wire harness conection backing off. idk how it happened but it was just barely on and not making a full conection. sometimes it would run fine then other times it would run real rough and die.

 

When you cleaned the throttle body did you take the TB completely off the car? or did you just clean the side that you can see? Have to clean both sides or the problem will still exist. Although seems like something other than a TB problem, But still, makesure to take theTB completely off and clean both sides

 

Whatever it is, it should be easy to fix as soon as you have the codes read with a scan tool.

 

Does your check engine light work? Clean air filter is a great place to start...

 

The air filter looks to be new... Yes, I took the TB off to clean it. It was pretty nasty in there but I shined 'er up all nice and pretty. It didn't do anything to fix my issue though. The check engine light works and the code reader came up with 0 results. I hooked it up 4 times to verify the lack of a code. The last time I hooked it up, I even started the Hummer before I hit "read code" and still didn't have any luck. I'm certain this is a fuel issue, due to the fact that it will start and run normally for the first 5 seconds before it starts sputtering. The fact that it didn't throw a code makes me more sure I have a fuel issue. It isn't a hit or miss problem, as I haven't been able to get it to run since the first time it failed. It's looking like ol Tanto is going to have to hitch a ride to the dealership, I'll let the extended warranty cover what I'm more and more convinced is going to be a new fuel pump... On a 65,000 mile truck. Peachy!

 

KentuckyRock,

I have been having the same issue but not nearly as severe. I have an 06' with around the same millage as yourself. My problem occurred about a month ago where I would turn the truck on and it would idle weird and drop in RPM's then stall after 10 minutes of slow driving. I took it to an independent mechanic who scanned it multiple times and no codes were displayed. We did a tune-up, changed the spark plugs, and the air filter as well. I believe everything has been fixed but I feel like the truck is idling a bit rougher than usual but will hold steady at light at around 6K RPM. I have not cleaned the throttle body yet but will do that next. Please let us know what you find because I think mine might have a very similar problem.

Does anyone else have any other ideas?

 

chek the connection where the wire harness plugs into the coil packs on each cylinder...one of them might be a little loose. happened to me before.

 

Possibly could be the purge valve? I posted a thread on the site here how to replace it with pictures. Not too bad of a job. The valve costs $50 from G.M. If you have them do it, it's about a $250 job. Ours idled perfectly after replacing. Don't know if this is your problem but just a suggestion.

 

I will have those checked when I take it into the shop. I am also going to have the throttle body cleaned as well. Unfortunately I live in San Francisco these days and do not have a garage to work on the car in. I know there are many threads on throttle body cleaning but actually how hard is the cleaning? Am I better having it professionally done?