H2 Mileage Dropped suddenly

[dwaxman1]

Okay, it has been awhile but I have an interesting thing happening to my H2..it used to get "ok" mileage but now all of a sudden is is sucking gas like there is no tomorrow, not sure why as we have not changed anything...I have a nasty squeal coming from the front as well, I believe that is the Serpentine belt but would that impact my mileage?? it is very odd... any suggestions?? and any suggestions other then buy more fuel John <img src='http://www.canadianhummerclub.com/forum ... rgreen.gif' class='bbc_emoticon' alt=':mrgreen:' />



btw i was running around 15-18L/100K before, now i am up to 22-23L/100K so some thing is not good and no check engine light

[Indy]

I'm getting 20-22 Liters with careful driving (I do have 37 Mud Terrains though). Not sure how anybody could get 15-18 Liters unless it is only highway driving. Did you check tire pressures? Maybe try cleaning the throttle body, injectors etc....did you notice a drop in power as well? Good luck finding the problem, although those numbers don't seem to be anything unusual for an H2. Try checking the fuel consumtion manually...

[Sugarphreak]

[quote name='dwaxman1' timestamp='1325432749' post='33982']

Okay, it has been awhile but I have an interesting thing happening to my H2..it used to get "ok" mileage but now all of a sudden is is sucking gas like there is no tomorrow, not sure why as we have not changed anything...I have a nasty squeal coming from the front as well, I believe that is the Serpentine belt but would that impact my mileage?? it is very odd... any suggestions?? and any suggestions other then buy more fuel John <img src='http://www.canadianhummerclub.com/forum ... rgreen.gif' class='bbc_emoticon' alt=':mrgreen:' />



btw i was running around 15-18L/100K before, now i am up to 22-23L/100K so some thing is not good and no check engine light

[/quote]



Maybe it is slipping over the alternator and when it does grip it has to spend more time charging the battery which puts a heavier load on the engine? Although that should throw a code for the charging system, so maybe not.



Could it be something else like a water pump or power steering pump seizing up and putting more load on the engine? Also causing squealing when there is too much load and it slips?



Or like my truck where the bearings when on the idler pulley seized up and exploded the assembly on the highway. I am sure I wasn't getting the greatest mileage before that and my belt was making all kinds of ominous noises.

[Archngel]

other than the obvious winter driving always take more gas that summer driving,, i noticed mine from 12-15l/100km jump to nearly 20-22l/100km, , more idling, foot a bit heavier maybe on start to warm up faster,, all together it adds up to more fuel comsumption..



So maybe only a natural recurance.

[JL]

Archngel is right mileage will definitely go down in the winter but that does seem like a lot... I usually see like 16-18L/100k in mixed driving. You know what I bet? See if you can spin the fan by hand when the engine is cold, I bet that fan clutch is seized up which would also explain the squeal!!



Depending on what the squeal sounds like, constant or intermittent or whatever, I bought a mechanics stethoscope and the thing works like a damn for finding these types of noises! Super cheap too I think it was only like $10-15 at Napa. A worthy tool!!

[collega]

My H2 "eats" normally 22-23L/100km and my driving habbit is not so bad so I try normally to drive economic way. I never managed to get even 20L/100km unless I am on the highway where I can get may be 17-18L/100km. So It looks like everything is not so bad for You. I don't know how You can get for regular city driving before 17-18L?

[Gadgets]

Mine is 19.7/100km solid, pretty much never changes. Your Tow/Haul button isn't stuck on or something is it? Having that on when not towing will apparently kill your mileage.

[JL]

That seems crazy you guys! This summer road-tripping my best tank was 14.8L/100km (first and last time I ever saw mileage like that though). I've got a set of mudders too not even highway tires... Mine is pretty well stock with just an intake, exhaust and Hypertech. Also replaced all fluids with Amsoil synthetics last Spring...



Try running a can of Seafoam through the engine and see if that makes a difference as I've always had good results with the stuff! But everyone says I drive like a grandma so could be that it as well...

[johnnyspikesH3]

OK i will take swing at this . As for the squeal : Bent pulley or seized ? Gas mileage : Plugged catalytic or other exhaust components . Theses should show codes i know. Hey, crazy things happen ! Derek has a lot of Mods and extra pounds on his Rig . For those who have seen it up close . They know . Most important Gang.. let's not rule out this . <img src='http://www.canadianhummerclub.com/forum ... feSpit.gif' class='bbc_emoticon' alt=':coffeespit:' />

[whitehumh2]

[quote name='dwaxman1' timestamp='1325432749' post='33982']

Okay, it has been awhile but I have an interesting thing happening to my H2..it used to get "ok" mileage but now all of a sudden is is sucking gas like there is no tomorrow, not sure why as we have not changed anything...I have a nasty squeal coming from the front as well, I believe that is the Serpentine belt but would that impact my mileage?? it is very odd... any suggestions?? and any suggestions other then buy more fuel John <img src='http://www.canadianhummerclub.com/forum ... rgreen.gif' class='bbc_emoticon' alt=':mrgreen:' />



btw i was running around 15-18L/100K before, now i am up to 22-23L/100K so some thing is not good and no check engine light

[/quote]



Hey D,



While there will be a drop in mileage due to the recent cold snap, it should not be that extreme. I had a similar experience on my H2 after getting stuck in a mud hole. (Yes, my mighty H2 actually got stuck!) A couple of weeks later I started to hear a squeak from the front right and noticed horrible mileage. In my case it ended up that the A/C compressor clutch had so much mud in it that it caused the bearings to seize and the tensioner to destroy itself along with the belt. Remember there is a separate belt for the A/C, that being said you can do a simple test, remove the A/C belt and see if the squeak goes away, if so then you need an A/C compressor clutch kit, a new tensioner and a belt.



Btw, I normally average 15-18l/100km and normally only touch the 22l/100km range when purely offroad!



Hope this helps,



Kev