Recently replaced the water pump, engine coolant sensor, secondary air valve, and thermostat and housing. Needless to say, the system was completely evacuated and therefore a ton of air in it. I know have coolant behind the engine side of the thermostat, coolant filled on the radiator side of the thermostat, radiator is filled, suction hose to reservoir and reservoir have coolant.

I filled the internal engine coolant passages between the radiator and the outlet side the beat I could by removing the hose from the radiator top side and pouring coolant in through the hose.

In my mind the air that could still be trapped in the system should be minimal, but I keep experimenting a temp gauge that goes to about 1/8 above cold and holds and then drops to cold and the dreaded AC Off message pops up.

I've tried to burp the system using the radiator cap off method, the lifting the front end method, and now the coolant system pressure test/fill kit method with the venturi assembly. The message still keeps coming up on the dash. When I used the vacuum method, I got the vacuum down to 20 inHg with the compressor connected and running and the lever open on the vacuum assembly. When I closed the compressor lever, it dropped to 10 or so. When I open the coolant line to allow the vacuum to draw coolant in, I have been able to get it to draw in 1/2 gallon before vacuum returns to normal. I like in Denver so high altitude and thin air.

Help please! I feel like I'm likely missing something simple or that there's a method that I haven't come across that will finish this and get rid of that AC Off message once and for all.

Thank you in advance for the expertise and direction!

2006 Hummer H2. I've changed plenty of headlights but have never seen one like this. What is the second bulb? I bought 9007 replacement bulbs but they won't fit into whatever this is. How do I replace my headlight??

My 2007 hummer h3 runs fine until u been driving for about an hour and a half then my check engine starts blinking and it acts like it was to stall out but don’t when I pull over and turn it off then back on it starts running fine need some help the mechanics can’t even figure out what’s wrong with it

23.5” lift on this junker. Center cap to bottom of fender

Looking for a 2005 H2 Headliner. Anyone have one that's in decent shape?

Thanks,

Woody

I have a 2010 Hummer H3 3.7 5L, the factory radiator is busted. It has bad leaks at the seams where the plastic meets the aluminum. Currently trying to look for an upgraded replacement, maybe one that’s full aluminum. But not sure witch brand to go with. Any recommendations?

Update: replaced the battery after initially thinking it was just a battery issue because the original battery was tested and was determined broken.

Car won’t start. Occasionally it will turn over but then die within 5 seconds. Weird clicking and rumbling noise heard around the engine and under the driver side. Won’t start in neutral either (suggested in previous post). Any ideas? Thank you

This is my first hummer. I read how impractical they are. Wawawa. This one is the 6.6 LBZ Duramax diesel with the Allison 6 speed transmission a 2003. It gets 18 to 20 miles per gallon. and it has 179,000 miles on it. I love it.

Can anyone guess the original color?

Old dog has about 225k on the odometer now, mods were installed about 20k miles ago and have been holding up great. Figured I’d share because we don’t see many of these mods on the platform.

List of (alleged) current engine modifications:
- Summit 8720 cam
- LS7 lifters
- Dual nested valve springs
- Comp magnum pushrods
- BTR Shaft rocker system (1.7 ratio)
- Felpro MLS head gasket 8.2cc

Feel free to ask any questions, or comment on the worsening mpg of a brick.

Got this for 7500$ with only 94k

Hey there. So I've been considering what vehicles for storm chasing, specifically the Hummer line up, should I use in the future when I can purchase one. So which one would be the best all-rounder for storm chasing; the H1, the H2, the H3, or the EV?

Going through very rough patch with the health of my parents and I inherited their cars, one is a 90k miles 2003 H2 with Magnusson supercharger. Has new radiator, kryptonite tie rods/sway bars, tires, backup camera, and some other things.

I guess I’m feeling out whether to get rid of it because I can’t maintain all these cars and the Hummer looks like the next logical one to get rid of

Is there anywhere you all would recommend to sell it to someone who loves hummers and would take good care of it / enjoy it? I’d hate to hand it off to a random dealership. Still on the fence about selling but figured I’d plan ahead if I decide to get rid of it. North Texas area for location

ETA: thanks everyone for the interest. Over the last couple days I think my mom’s condition is deteriorating and this might be her last few weeks alive.I’ll come back later with pictures and more info later when able, but for now I need to focus on her. Thanks again

I’m in need of a fuel pump. Any suggestions?

Anyone know how to reset or re-stage these connectors so they’re ready to accept the new fuse box? I’m replacing the underhood fuse box on my 2008 Hummer H3, but the connectors won’t seat properly. I heard there are locking tabs or levers that need to be pulled out, but I can’t figure it out. Any help or videos would be appreciated!

When test driving this Hummer, the brakes were very spongy I noticed immediately. The first half way pressing the pedal did nothing till you reached the bottom pretty much. But the scary/safety part I noticed is it was almost like the breaks were giving out. This happened what seemed randomly where I would hit the breaks all the way down and nothing would happen, then it would almost press down even lower than it normally does and there would be grinding and slow braking. Outside of this is was breaking normally but it happened three times in only the span off 20 minutes driving it. I would really like to know if anyone else had experience with this and knew what the issue might be, and estimated cost to fix is. I really loved everything else about this vehicle except that, which is a very big flag with it being such a safety hazard and having me scared to be driving the vehicle.

Step-dad states Hummer H2 would turn over but then die right away. Weird machine gun noise when attempting to do it myself. Battery is good. Any suggestions? Fuel pump?

Thinking of finally fulfilling my child hood dream and getting a h3 but I NEED spinning rims 20’s max real back in the day when 20’s was extreme I’m fine with anything under 20. Is there any place that sales used spinners or anything because to be honest I wouldn’t want this car with out getting spinners and I’ll also be throwing some LED underglow 100%

Anybody interested? SoCal

Fell back in love with it after finally getting it up and running right.

The high mileage comes with its share of problems, but one of the most stubborn ones had to have been diagnosing an intermittent air conditioning problem.

This might be helpful to you guys:

I had a faulty reading from the engine coolant temperature (most likely caused by frayed wiring and not necessarily the sensor) and I've concluded that the sensor must trip the compressor to shut off if it reads the engine running too hot. My temp gauge was bouncing left and right and would throw out sporadic "Low Coolant Level" and "Engine Overheating" notifications and the air conditioning would go warm and then eventually get cool again.

I still have some issues to tackle, but its the nature of the beast.

Aside from that, I refreshened the interior, added new shocks, brakes, and tires, although its still really bouncy (which I think is due to the wrong springs installed by the previous owner when he converted from air ride)