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NHTSA — Engine Problems

2007 Hummer H3 (Page 1 of 2)


hardly worth mentioning
Crashes / Fires:
0 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
73,254 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2007 Hummer H3 engine problems

engine problem

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2007 Hummer H3 Owner Comments (Page 1 of 2)

problem #29

Sep 102010


  • 7,000 miles


The contact owns a 2007 Hummer H3. While the vehicle was parked, the key became stuck in the ignition and could not be removed. The vehicle was towed to a dealer where it was diagnosed that the ignition cylinder failed and needed to be replaced. The dealer made many attempts to repair the vehicle, but the remedy failed. In addition, various electrical functions failed and a burning odor was noticed. The manufacturer was notified of the failure. The failure mileage was 7,000.

- Steamwood, IL, USA

problem #28

May 312016


  • 140,000 miles
My Hummer stalls and dies at various times. This is dangerous and know one can seem to tell me why it dies while driving. I take great care of my truck and me I have metal shavings in oil. Dying in an intersection with children is dangerous. This needs to be addressed.

- Southaven, MS, USA

problem #27

Apr 092016


  • 103,306 miles
The vehicle just lost power and almost lost ignition while driving 50 miles an hour. Diagnostic code state, misfire in cylinder one. Valve springs ( rocker arm) are breaking prematurely causing a leaking valve problem. Mechanic also noticed other springs were fatiqued causing a looser than normal seating. GM service manager mention a spring problem on 2006 2007 rendevous. One of the largest complaints with the Hummer 3 is this leaky valve syndrom which the dealers know about. Some occuring with the vehicle having only 30,000 plus miles.

- Southfield, MI, USA

problem #26

Feb 252016


  • 110,488 miles


Bought 2007 Hummer H3 at the end of February as is in Chicago at net motor cars addison Illinois for 14000 and drove it home 150 miles away and was told by dealer to take it in to GM dealer and have my ABS system flashed by them and all warning lights will go away GM poages had my car for two weeks cost 560 dollars to repair then a day later check engine light came on took it to a shop and they said if GM had it checking for codes they should have seen the wire if they had it on machine looking for codes because that wire had to be in place to read the codes so he told me to take it back to them to repair it for free. I told him no for him to go ahead and fix it for a hundred because if I take it back to GM poage what other trick do they have up there sleve if they fix it. So he did and it showed multiple misfires and a steady misfire on cylinder 5 told them to fix it costing $1929.90 car has been in two different shops two weeks at the GM dealer poage auto mall in Decatur Illinois very disappointed on there behavior of being shady if they had it hooked up for two weeks on a code reader why didn't they see misfires. Will never do business with them ever they lost a 2000 dollar job and my future services like changing oil ect. This is bad business. Getting my car this week from South shores audo which will have my business in the future. GM or at least Decatur poages auto mall should be investigated by trying to screw over a woman and who else they can they pulled wire so I would bring back to get radio replaced as I was because I only had so much money to replace I think when I was going to bring back in for a refurbished trade in radio they were going to install it then hook wire back up and surprise me with the misfires and a probably 3000 dollar job. Also South shores auto told me nothing wrong with radio

- Decatur, IL, USA

problem #25

Nov 122014


  • miles
First the entire computer system stopped working. Had to replace thr PCM. Then my blower started throwing hot air when on cold. Had to install separate to resolve that issue. Had to re-build the transmission twice due to leak of coolant into the transmission. This truck has been a nightmare so far.

- Richmond, TX, USA

problem #24

Mar 012014


  • 74,000 miles
The contact owns a 2007 Hummer H3. The contact stated that the engine was defective. The engine failed to start numerous times intermittently. The engine started after waiting ten minutes and the anti-theft light illuminated. The vehicle was not diagnosed nor repaired. The manufacturer was notified. The VIN was unknown. The failure mileage was 74,000. Updated 04/22/16

- Moore, SC, USA

problem #23

Feb 052016


  • 120,000 miles


The radiator has a crack in it which is a very common issue...needs to be recalled. My H3 was idling rough and would shut off. Had to replace throttle body and solenoid. The anti-theft acts up and the H3 won't start have to wait 10 minutes. The ac blower and connector burnt paid for it to get fixed then the recall comes out 7 days later....still haven't been refunded for that. I have all the issues on my 2007 H3 that should all be recalled and fixed at GM expense. Sunroof drains get clogged all the time and have water leak onto the floor which makes the ABS light trigger on and off. Issue after issue which GM doesn't take any responsibility for. It looks like it's time to sell the Hummer H3!!

- Tallahassee, FL, USA

problem #22

Dec 012014


  • 94,000 miles
Rebuilt transmission twice cleaned throttle body replaced exhaust manifold two O2 sensors replaced the radiator the heater core a fuel pump relay and this engine light still will not turn off it says torque converter clutch solenoid I'm disgusted already GM fix ur [xxx]. information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Houston, TX, USA

problem #21

Nov 112015


  • miles
Takata recall miss fire ignition coil theres way to many complaints about this if theres nothing done about this its the last time im buying a GM automotive to get it fix cost almost $3000 dollars thats not good for your business

- Wichita, KS, USA

problem #20

Aug 212015


  • 140,000 miles
The contact owns a 2007 Hummer H3. The contact stated that the check engine warning light illuminated. The contact received notification of NHTSA campaign number: 15V421000 (visibility) and stated that the parts needed for the repair were not available. The contact stated that the manufacturer exceeded a reasonable amount of time to the recall repair. The manufacturer was made aware of the failure. The failure mileage was 140.000.

- Raleigh, NC, USA

problem #19

Oct 022014


  • 100,000 miles


While driving at 65 miles per hour the vehicle dash lit up all service lights the vehicle went into reduced power mode not allowing the vehicle to exceed 40 mph and ABS sensors came on staying traction fail, ABS fail, began to stutter and stall. Took to shop. Vehicle running codes for spark plugs, replaced spark plugs. Few weeks later did it again, this time saying throttle body. Replaced it, a month later did it again, each time in major traffic having to pull off roadway to avoid an accident. This time says misfiring, throttle body, ABS, TPMS, thermostat, etc. Take it to have compression test run and system says cylinder failure. Do research on issue and find that there are hundreds of complaints about this online having caused accidents and thousand of dollars spent by consumers after having accidents but no known fatality so GM will no recall or honor the issue repairs. Almost all of them happening at 100K miles.

- Mount Washington, KY, USA

problem #18

Sep 132013


  • 65,000 miles
Vehicle would not start called dealership where car was purchased - replaced ignition switch after diagnosis. Since then have had repeated episodes of vehicle ignition/electrical just shutting completely down on different occasions. I could be sitting or approaching a stop light vehicle shuts down upon taking off or idling down, vehicle also shuts down when making turns as well. It occurs so infrequently and has no pattern but it is indeed a safety concern because I have to put on the flashers and take time to restart the engine all before someone runs into me.

- Raleigh, NC, USA

problem #17

Feb 022015


  • 66,790 miles
Engine check light came on for very short period of time then went out. About a week later it came on again. Went to Chevy dealer who ran a quick code check which indicated the number 5 cylinder was misfiring. The Chevy dealer indicated the engine/power train warrranty had expired and the problem could be from injectors, plugs, coil and valves. Initial computer check would cost $135. Vehicle is sitting in my garage awaiting money to get it checked.

- Fairfield, CA, USA

problem #16

Dec 262014


  • Manual transmission
  • 56,800 miles
The contact owns a 2007 Hummer H3. While driving approximately 40 mph, the vehicle shook violently and stalled without warning. The vehicle could not be restarted. The vehicle was towed to the dealer where it was diagnosed that the engine or the cylinder needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 56,800. Updated 03/10/15 updated 6/17/2015

- South Plainfield, NJ, USA

problem #15

Jul 012014

H3 5-cyl

  • 60,000 miles
Just had my Hummer in 2 weeks ago at the GM dealership to have the ignition switch replaced. Had been dealing with it stranding me and my kids for 10 minute periods long enough. ( sometimes longer) while it was in there we also had to get the radiator replaced due to it being cracked. Now 2 weeks later my check engine light and traction light have come on. The traction light saying service sab system. After reading all the Hummer problems I can not believe that there was not a recall on both the ignition switch and radiator. The ignition switch being faulty put me and my kids in situations in places for long periods of time that were not safe and at times we were very cold since we can have below zero weather in Colorado. The ignition not recognizing the key causing the anti theft system to activate is recall issue and GM you should be taking responsibility for this!!

- Ault, CO, USA

problem #14

Aug 182014

H3 5-cyl

  • 57,534 miles
My vehicle has a cracked radiator and according to other Hummer owners this is a common defect that happens to these vehicles. His over heating cuased me to pull over on a busy highway were I could of been hit and killed, total failer of vehicle electronics, GMC does not want to work on the vehicle that is not under warranty, because of the many problems wth this vehicle. This crack is were it is wearing near the motor.

- Palm Bay, FL, USA

problem #13

Jul 282014

H3 5-cyl

  • 73,550 miles
I purchased this vehicle, new in July 2007. Since that time I have meticulously maintained the vehicle. On 7/28/14, parked at home. Got out and smelled coolant vaporizing (distinct smell). I am a retired master mechanic, with 44 years experience (currently age 60). I examined the radiator, rinsed it off and dried it, pressurized the system to discover a hairline crack in the upper, plastic tank of the radiator in an area with no impingement of other components, no trauma, and no rough use, ever. I caught it at the very first manifestation, solely by the smell. Examining the vehicle closely to discover while my radiator had only this hairline crack in a location of no-stress and no impingement of other components. Research further to discover this is a very common problem with the H3, from 2006, 2007, 2008 and 2009 models all in the 50,000 to 100,000 mile readings. The replacement of the radiator at local GM dealer, with cooling system service was extremely expensive as the replacement of the radiator requires the receiver dryer of the air conditioning system to be disconnected which requires discharge and recharge of refrigerant R124A. I saved the defective radiator. There is no other wear nor damage. The internal cores were clear and clean like new. No obstructions, dirt nor wear. In other words I was forced to replace a perfectly good radiator for 1 hairline crack on the upper plastic tank. This repair, including all courtesy discounts from the selling dealership, as I had been an auto repair shop owner and loyal customer for 30 years of my life, cost me $966.57. NHTSA should do a formal defect investigation on all the Hummer H3 models and any / all other GM like-type vehicles with the plastic tank radiators which could cause a serious accident or death.

- Palm Beach Gardens, FL, USA

problem #12

May 022011


  • 55,000 miles
Radiator had small leak, has since increased over last 3 years. Not covered under warranty and every H3 owner knows this is a defect that needs to be recalled.

- Warwick, RI, USA

problem #11

Apr 012014


  • 85,000 miles
Less than 1 year ago, I had the radiator and transmission replaced in my vehicle. I have recently noticed the smell of antifreeze coming from my hood after long trips. The radiator that was installed in my vehicle 10 months and 8K miles ago has developed a crack in the top tank. There is dried coolant spray across the top of my engine and a crack forming right behind the lip of the frame of the truck.

- Deerfield Beach, FL, USA

problem #10

May 012013


  • 70,000 miles
My radiator tank cracked right across the top compromising my cooling system. This turned into a bigger problem as the transmission oil cooler was not operating correctly and eventually destroying my transmission. I had to spend over $2K to have a refurbished tranny and new radiator installed.

- Deerfield Beach, FL, USA

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