H3 Idling Rough - Head Problems?

Hummer Forums Hummer Classifieds Photo Gallery Member List Calendars Search Forum FAQ Contact HF Sponsors
Hummer Lineup Hummer News Hummer Recalls TSBs Timeslips Register Login

H3 Idling Rough - Head Problems?

Printable Version

Hummer Forum >> Hummer Lineup >> Hummer H3 >> H3 Frequently Asked Questions >> Head and Valve Problems. >> H3 Idling Rough - Head Problems?

Page: [1] 2 next > >>

Message

<< Older Topic Newer Topic >>

H3 Idling Rough - Head Problems? - 1/15/2007 12:00:56 PM

PhxRealtor

Posts: 4
Score: 0
Joined: 1/4/2007
Status: offline

My H3 with about 17,000 miles started to idle rough a while back. Otherwise it seems to run good. No real loss in power. I'm wondering if this means I have head/cylinder problems? It seems to get worse if I use certain electrical items when idling, like power windows or step on the brake etc.. Just wondering if anyone has any insight on this. Mine was one of the earlier 2006's built.

_____________________________

2006 Victory Red H3 Adventure
2007 Jeep Wrangler 4 Dr Unlimited

Post #: 1

RE: H3 Idling Rough - Head Problems? - 1/15/2007 12:41:37 PM

importkiller

Posts: 7254
Score: 0
Status: offline

I think everyone that has had teh head/valve issue also had a check engine light for a misfire. The rough idle condition you are having will get worse when elctrical items are used just cause taking more juice will lower the rpms slightly and cause more rough idle. I would check the obvious first, air filter, type of fuel, normal stuff like that.

_____________________________

(in reply to PhxRealtor)

Post #: 2

RE: H3 Idling Rough - Head Problems? - 1/15/2007 2:35:00 PM

Dennis

Posts: 7584
Score: 0
Status: offline

Replace the MAF and see if that fixes it..

(in reply to importkiller)

Post #: 3

RE: H3 Idling Rough - Head Problems? - 1/15/2007 3:35:51 PM

importkiller

Posts: 7254
Score: 0
Status: offline

the MAF should send a code as well I think Dennis? also it's kinda expensive to replace one to to see if it fixes it. I would definately bring it to the dealer for that.

_____________________________

(in reply to Dennis)

Post #: 4

RE: H3 Idling Rough - Head Problems? - 1/15/2007 3:58:38 PM

LawWyfe

Posts: 1565
Score: 0
Joined: 11/15/2006
Status: offline

As previously stated in several posts, my "check engine light" did NOT ever come on (thru a week of driving it after it began to idle ROUGHLY)....I only knew it was an engine misfire code thru OnStar's informing me.

_____________________________

2006 Hummer H3 Boulder Gray
Simple and understated and not all tricked out!
Sometimes less is better......OK...some BLING since I joined here!

(in reply to PhxRealtor)

Post #: 5

RE: H3 Idling Rough - Head Problems? - 1/15/2007 4:07:05 PM

importkiller

Posts: 7254
Score: 0
Status: offline

thats strange because the only way onstar would know of a misfire is if the engine sent a code, which also should have tripped the light at the same time. thats very strange...not saying your a lier...just saying thats odd that the light didn't go off.

_____________________________

(in reply to LawWyfe)

Post #: 6

RE: H3 Idling Rough - Head Problems? - 1/15/2007 5:36:06 PM

LawWyfe

Posts: 1565
Score: 0
Joined: 11/15/2006
Status: offline

Honest engine ( being PC LOL) hun, the light never came on. In fact it happened 3/4 of the way to the mountains immediately after we had just done a refuel, so we thought "OK, maybe we got bad gas." The rough idling continued thru another couple tanks and us thinking maybe we should put some additive in it???? Coincidentally when we made our destination, it happened to also be on the same date my monthly OnStar email report comes...it contained an "emissions problem" message and to call Onstar for which I did. They then ran a diagnostic test and said all they could tell me is the diagnostic "showed an engine misfire at some point and to proceed to my nearest dealer." Of course no dealer to proceed to in the mountains, so we chanced it until we got home and I took it into the dealer the next day...got the dreaded head news. OK, so does my check engine light not work properly?????

< Message edited by LawWyfe -- 1/15/2007 5:37:00 PM >

_____________________________

2006 Hummer H3 Boulder Gray
Simple and understated and not all tricked out!
Sometimes less is better......OK...some BLING since I joined here!

(in reply to importkiller)

Post #: 7

RE: H3 Idling Rough - Head Problems? - 1/15/2007 6:06:40 PM

shortbus

Posts: 3602
Score: 0
Joined: 6/27/2005
Status: offline

quote:

ORIGINAL: LawWyfe

OK, so does my check engine light not work properly?????

try cutting some random wires under the hood, that should tell you if the light works or not. i'd start with a plug wire, or something coming off the injection or air intake, just not the battery cable . . . .

(in reply to LawWyfe)

Post #: 8

RE: H3 Idling Rough - Head Problems? - 1/15/2007 6:20:13 PM

LawWyfe

Posts: 1565
Score: 0
Joined: 11/15/2006
Status: offline

LOL OK SB...are ya just messin with me too? And just what do I do then after I cut these wires?? (besides tape em back together LOL)

_____________________________

2006 Hummer H3 Boulder Gray
Simple and understated and not all tricked out!
Sometimes less is better......OK...some BLING since I joined here!

(in reply to shortbus)

Post #: 9

RE: H3 Idling Rough - Head Problems? - 1/15/2007 6:55:19 PM

shortbus

Posts: 3602
Score: 0
Joined: 6/27/2005
Status: offline

now that i think about it, it would probably be easier to just cut the serpentine belt. then you can take it to the dealer and have it replaced under warranty, as well as whatever else breaks once you do that. but, you'll at least know if the check engine light works . . . .

(in reply to LawWyfe)

Post #: 10

RE: H3 Idling Rough - Head Problems? - 1/15/2007 8:06:26 PM

kild1

Posts: 852
Score: 0
Joined: 12/26/2006
Status: offline

LawWyfe

just unplug a sparkplug wire and drive it around some..this should set the light off

_____________________________

07 H3X Sonoma Red Metallic

(in reply to shortbus)

Post #: 11

RE: H3 Idling Rough - Head Problems? - 1/16/2007 8:22:11 AM

LawWyfe

Posts: 1565
Score: 0
Joined: 11/15/2006
Status: offline

Thanks guys...I am thinkin this would be my best bet and least damaging in light of my lack of mechanical knowledge LOL...my luck I'd cut a wire that holds everything together LOL

_____________________________

2006 Hummer H3 Boulder Gray
Simple and understated and not all tricked out!
Sometimes less is better......OK...some BLING since I joined here!

(in reply to kild1)

Post #: 12

RE: H3 Idling Rough - Head Problems? - 1/16/2007 9:11:26 AM

HummerGuy

Posts: 6684
Score: 0
Status: offline

quote:

ORIGINAL: LawWyfe

Thanks guys...I am thinkin this would be my best bet and least damaging in light of my lack of mechanical knowledge LOL...my luck I'd cut a wire that holds everything together LOL

Just put Diesel fuel in your gas tank. You should find out REAL quick if your check engine light works......

(in reply to LawWyfe)

Post #: 13

RE: H3 Idling Rough - Head Problems? - 1/16/2007 1:21:30 PM

importkiller

Posts: 7254
Score: 0
Status: offline

easiest way to see if your check engine light works is to not put the gas cap back on. You'll get the light for that too. I've had that happen a few times to me already.

_____________________________

(in reply to HummerGuy)

Post #: 14

RE: H3 Idling Rough - Head Problems? - 1/16/2007 1:25:45 PM

shortbus

Posts: 3602
Score: 0
Joined: 6/27/2005
Status: offline

quote:

ORIGINAL: LawWyfe

Thanks guys...I am thinkin this would be my best bet and least damaging in light of my lack of mechanical knowledge LOL...my luck I'd cut a wire that holds everything together LOL

WHOOOOOAAAA - i wasn't serious when i said cut wires under the hood (but the belt comment was semi-serious). now i'm gonna lose sleep thinking that somewhere, there's a disabled hummer because of my advice . . . .