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NHTSA — Engine Problems

2006 Hummer H3 (Page 2 of 2)


hardly worth mentioning
Crashes / Fires:
0 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
84,089 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.

2006 Hummer H3 engine problems

engine problem

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2006 Hummer H3 Owner Comments (Page 2 of 2)

« Read the previous 20 complaints

problem #13

Jan 092014

H3 5-cyl

  • 125,000 miles


Owner the car since 2006 with no problems--regularly maintained, 125,000 miles. After a recent long trip my wife took it to the shop where she was told the engine had "low compression." The shop was trusted 100% and been used for decades. Service manager said they would see what they could do about the low compression and that they would have to check each of the pistons. After the review, the manager said he had bad news, that the car needed to be traded in/sold immediately and not to drive it until it was. I verified the results with 2 other mechanics that the 5 cylinder H3S lose compression out the blue--common among 5 cylinder H3S. The shop manager basically told me that I need to sell/trade in the vehicle, but not to drive it until I had done so, apparently this issue has happened to 06 H3S religiously where the compression diminishes and leads to the engine dying.. it's a possible to buy a used engine with the possibility that the compression could die again. Needless to say, we feel like we've been punched in the gut by Hummer. How can a car perfectly maintained all of a sudden have "low compression" and lead 3 professionals to advise us to sell it L it as soon as possible? this had to have been known by Hummer and they did nothing about it. Meantime, we are probably over/under on the vehicle and will have to get rid of it.

- San Antonio, TX, USA

problem #12

Nov 102009


  • miles
First of all, the date of the incident is very vague considering it's been happening most of the life span of the vehicle. Ever since the vehicle reached 30,000 miles the check engine light has been going on and off periodically. Now there is around 85,000 miles and I can honestly say the check engine light has been on for most of the life of the car. The code is always P0300. This is due to a random misfire in the cylinder heads. I have had this car long enough to say this typically happens during idle. This car has always had a rough idle. I would say ten percent of the time it's a smooth idle. I always use good gas, clean oil and up to date maintenance on this vehicle and I never stress the engine due to it's feeling of it being so fragile. Going online I am astonished to find so many with the same exact problem. GM had the same recall on the inline 5 cylinder canyon cylinder heads. This is the same problem we are having with our inline 5 cylinder engine heads. GM needs to put this on recall. Fix their mistake and keep this check engine light from going on every time I park my car, start my car or simply idle. Many would be grateful if this was recalled.

- Philadelphia, PA, USA

problem #11

Sep 202013

H3 5-cyl

  • 120,000 miles
Blower motor quit working. Took to dealer said needed motor wiring harness and resitor. They said the wiring harness caught fire and fused together. Cost of $300 to fix. Fire hazard.

- Lexington, KY, USA

problem #10

Jun 012013


  • 80,000 miles


The contact owns a 2006 Hummer H3. The contact stated that the vehicle would not accelerate over 50 mph. In addition, the vehicle would sporadically stall with the illumination of the check engine warning light illuminated. Also, the vehicle would overheat when the failure occurred. The vehicle was taken to a mechanic where a diagnostic was performed. The dealer advised that the catalytic converter, air sensor, coil springs, and the spark plugs needed replacing. The vehicle was repaired but the failure persisted. The failure mileage was 80,000 and the current mileage was 87,000.

- Greensboro, NC, USA

problem #9

Aug 272013

H3 6-cyl

  • 71,000 miles
The check engine came on and I took it to my dealership to have it checked out.they performed a diagnostic that located the failure at the engine head cylinder (engine missfire). The vehicle was not repaired. The manufacturer was contacted and denied assistance with the repair because the vehicle warranty was expired. The mechanic stated it was due to an inferior soft metal used to manufacture the heads which caused a loss of combustion when the engine was idling. The blowback at idle was what was causing the engine light to illuminate. Mechanic also stated this problem was a recurring problem in this 5cyl engine which is the same engine that is in the Colorado pickups and is covered under a GM recall in the pickups but not the Hummer. The mechanic stated that the issue will only get worst. Please help as I was given a price to repair of approx. $3183 if I was going to pay for the repairs myself at the dealership. What can a person do when this is a known mfg defect, many complaints about this issue with no recourse.

- Peoria, AZ, USA

problem #8

Jul 252013


  • 83,000 miles
The contact owns a 2006 Hummer H3. The contact stated that the temperature gauge had increased several times and when he inspected the vehicle, he found radiator coolant leaking from the radiator top seal. The vehicle was not repaired. The manufacturer was not made aware of the he failure. The failure and current mileage was 83,000.

- Horizon City, TX, USA

problem #7

May 222013

H3 5-cyl

  • 88,768 miles


Came out of work to find a puddle of coolant on the ground. Radiator plastic cracked. Fluid is on fan and throughout engine compartment. Searched on google and found this is a known issue. GM dealer and customer service acknowledged this is a common issue, however would do nothing about it.

- Lakewood, CO, USA

problem #6

Mar 292013

H3 5-cyl

  • 101,000 miles
The service technician diagnosed a cracked radiator, which is a know Hummer H3 issue. They have asked for $850+ to fix what is a known design flaw.

- Sachse, TX, USA

problem #5

Mar 072013

H3 5-cyl

  • 42,000 miles
I went in to dealer for what I called a fluttering periodic idle. They took a look $200 later told me I had misfire in #2 and #5 and needed new head. You can imagine my comments and he said it is common he just did one last week on the same year and type H3! well I was in touch with GM - the car is out of warranty but low mileage. They did cover a portion and I was responsible for the rest. Well I pick up week later. Was told it was test driven and runs great. I told them it ran great before just the fluttering idle when I stopped at a light. They said you are all set.. many bad words escaped my mouth when I drove home and it was not fixed. The vehicle still drove the same way it did before and the flutter was still there, . so now I have to bring it back again and I made the tech get in the vehicle so he knew what I was talking about and he said well it was brought in for a misfire. Uhhh no it was not. Why has GM not done any type of recall on this if it is known problem. Feel like they don't care since the vehicle is not made anymore what does it matter to them. I could continue but am limited to characters.

- Chicopee, MA, USA

problem #4

Dec 262012

H3 5-cyl

  • 79,998 miles
The check engine light went on and off. The vehicle was taken to a mechanic who diagnostic as cylinder #1 misfire. Compression test failed due to cylinder leakage. The main problem was to at the time of manufacturing the engine soft metals were used with the heads. I was told I need to replace cylinder head and related parts. Contacted GM Hummer division informed them of my problem with my 3.5L, 5 cylinder engine and ask them for assistance since they did a special extended warranty for the 2006 Colorado and canyons with the same engine problems. They refused to help.

- Raymore, MO, USA

problem #3

Jul 012012


  • 103,000 miles


The contact owns a 2006 Hummer H3. The contact stated that while driving approximately 65 mph, the vehicle suddenly stalled. The check engine light illuminated on the instrument panel during the failure. The vehicle was taken to the dealer for a diagnostic test. The technician stated that the engine's cylinder head would have to be replaced. The vehicle was not repaired. The approximate failure mileage was 103,000.

- Orlando, FL, USA

problem #2

May 172012


  • 65,934 miles
The contact owns a 2006 Hummer H3. The contact was traveling 50 mph when the smell of coolant emitted inside of the vehicle and white smoke was visible from under the hood. The check engine warning light illuminated intermittently with the failure. The contact confirmed that the engine was over heating. The vehicle was taken to a private mechanic who confirmed that the radiator needed to be replaced. The manufacturer was contacted. The vehicle was not repaired. The failure mileage was 65,934 and the current mileage was 65,936.

- Rayne, LA, USA

problem #1

Mar 012012


  • 70,000 miles
The contact owns a 2006 Hummer H3. The contact stated that the instrument panel displayed a warning message that read ┐reduced power service stabilizer system tracking failed┐ and the vehicle failed to accelerate beyond 40 mph. The vehicle was taken to the dealer and was repaired. The failure continued. Both the dealer and the manufacturer were unable to further diagnose the failure. The failure and current mileages were 70,000.

- Tallahassee, FL, USA

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