Problems · by component
2006 Hummer H3 engine problems
52 owner complaints to NHTSA about the 2006 Hummer H3 cite engine, 14% of all 362 complaints for this model year.
Complaints
52
14% of all complaints
Crashes
0
Reported by owners
Fires
1
Reported by owners
Injuries
0
Reported by owners
What owners say about the engine
Verbatim from NHTSA complaints, newest first
“On the electrical, I refer to my air conditioning and heater. When I have my air selection to coldest and I drop 1 click for it to be less cool, my heater turns on and at times it smells like something burning. I have to turn it off . On the engine, after I hit 90,000 miles, I have to fill up my engine oil every 2-3 weeks because my vehicle is burning it quick or something. It doesn't leak oil at all. The oil just seems like it's burning somewhere and I ha e to be waisting money to buy oil $30 to $60 a month. Please help. Thank you!”
“Was heading home from work and the 2006 Hummer H3 shut off while traveling in the middle of traffic was able to cruise in Nuetral until I could stop to start car again started car and yet again I receive a cylinder misfire code which has been repaired on multiple attempts still no success. I am going to end up either crashing or an emergency vehichle will be trying to get by and I can't move because the motor shut down.”
“Engine has very bad rough idle after multiple attempts to repair will get a misfire code often that goes on and comes off engine has rough idle to the point where truck shuts off completely while waiting at traffic light. My safety is at risk as this could happen during driving causing a wreck or during a light change when the emergency vehicles need me to move over and my truck don't run. Vehicle was inspected by multiple mechanic and still has issues. Check engine light comes on at time of motor failure or when rough idle.”
“P0305 CEL CODE CAME ON AND TOOK IT TO A MECHANIC. THEY DIAGNOSED THE ISSUE AND DID A COMPRESSION TEST WHICH PRODUCED RESULTS OF CYLINDER 5 HAVING 70 PSI AND THE OTHER CYLINDERS WERE NORMAL. DETERMINE THAT THE VALVES SEATS ARE BAD AND IT IS A COMMON ISSUE ON THE HUMMER H3. TOTAL COST FOR REPAIRS WAS PROJECTED TO BE $9,000 FOR ALL PARTS AND LABOR.”
“P0300 CODE. ENGINE MISFIRE. THE HUMMER FORUMS I'VE RESEARCHED SAY IT'S A COMMON PROBLEM IN THESE CARS, MANUFACTURED BEFORE MARCH 31, 2006. IT SEEMS THE ENGINE HEADS DO NOT HAVE PROPERLY HARDENED VALVE SEATS. AGAIN, I'M FINDING THIS IS A COMMON PROBLEM AND GM IS FULLY AWARE OF IT.”
“I HAVE OWNED THIS CAR FOR 10 YEARS. ITS ALWAYS GIVING ME PROBLEMS. ESPECIALLY THE ELECTRICAL AND ENGINE. I'VE GOTTEN 3 NOTICES IN THE MAIL FOR RECALLS AND GM HAS IGNORED MY REQUEST. AT THIS TIME I AM HOLDING THEM RESPONSIBLE BECAUSE MY HUMMER H3 IS ALWAYS IN AND OUT OF THE SHOP AND DONT FEEL LIKE IVE GOTTEN THE VALUE I DESERVE ON MY PURCHASE. PLEASE GIVE ME CALL AT [XXX]. IMY NAME IS [XXX]. EVEN THOUGH THERE ARE NO MORE HUMMER DEALERSHIPS AND NO ONE SPECIALIZES IN THE CARE OF THIS VEHICLE, I HAVE TAKEN COMPLETE CARE INSIDE AND OUTSIDE OF MY INVESTMENT AND HOPE TO GET SOME TYPE OF LEEWAY IN THIS MATTER. THANK YOU. *CC *TR”
Showing 6 of 52 reports. Read every report on NHTSA.gov.
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 10, 2026NHTSA vehicle page
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.