2004 Hyundai Elantra Problems

What owners report

Owner complaints for this model year center heavily on the front passenger air bag occupant classification system: adults seated in the right front seat frequently report the "passenger air bag off" indicator staying on, so the bag would not deploy. A smaller but consistent group of complaints covers engines that stall, overheat or shut off while driving, plus individual reports of unintended engine racing, clutch wear at low mileage, and seat belts that will not retract. Many air bag complaints were filed early in the vehicle's life, while several engine, brake and seat belt reports come in well past 60,000 miles.

1. 1
   Air bags

   Passenger air bag off light stays on with an adult seated

   • 74 complaints (41%)
   • median 10,000 mi at 1.2 yrs old (43 state mileage)
   • 4 mention a crash, fire or injury
   • filed 2004–2019

   Owners describe the "passenger air bag off" or air bag warning light staying lit or switching on and off while an adult is in the right front seat, in some cases after a dealer said the system was working to specification. Several reports involve adults well above the weight threshold in the owner's manual, and some describe the light changing state while driving around corners or up hills. Others say the light never comes on at all, or that a dealer wanted to charge for a seat sensor or seat replacement; a few mention the OCS reprogramming campaigns and that the light returned afterwards. Many reports come from vehicles with very low mileage, often under 5,000 miles and sometimes within the first year, though the light is also reported between roughly 50,000 and 85,000 miles.

   Recall 05V479000Recall 05V395000Recall 03V3220004 related service bulletins

   What to check: Sit an adult of known weight in the right front seat with the key on and confirm the passenger air bag indicator reads on, and check whether the OCS reprogramming recalls were completed. Ask for service records of any air bag control unit or OCS work.

   2 excerpts from owner complaints in NHTSA records

   “My 19 years old daughter's weight is not less than 56.4 pound. It showed displayed passenger airbag off while the seat was occupied. I think the alignment of ocs is off. It needed to be adjusted according to the specifics set for 56.4 or less. I think the car setting is higher than 56.4 pounds. I took my car to my dealer during the 7500 mile service and I mentioned about this problem to service manager. I got a response from them on the invoice. …”

   NHTSA complaint #10102389, filed 2004-12, 8 miles

   “Since I purchase the car in aoril of 2004, the passenger air bag indicator continues to read air bag off when a passenger is seated in the front seat who weighs over 56.4 pounds through about 160 pounds. This is recall number 03v322000, Hyundai recall no. 062. The manufacuturer will not fix the problem unless I sign a release which does not incidate anything about the air bag working with someone seated in the front passenger seat weighing more than 56.4 pounds. …”

   NHTSA complaint #10102425, filed 2004-12, 14 miles
2. 2
   Air bags

   Air bags did not deploy in a crash

   • 26 complaints (14%)
   • median 63,000 mi at 6.0 yrs old (19 state mileage)
   • 20 mention a crash, fire or injury
   • filed 2004–2019

   Complaints describe frontal, side and rollover-type impacts in which the driver or passenger air bags did not deploy, including cases where the vehicle was declared a total loss and occupants were injured. Some owners link this to the occupancy sensor warnings they had reported earlier, and others say they never received a recall notice. Dealers and the manufacturer are described as inspecting the vehicle or offering no assistance. Reported across a wide mileage range, from near-new vehicles to those well over 60,000 miles.

   Recall 03V322000Recall 05V3950002 related service bulletins

   What to check: Verify the air bag warning light behaves correctly on a test drive and that all air bag recalls are closed for the VIN; a history report or dealer VIN check can show outstanding campaigns.

   2 excerpts from owner complaints in NHTSA records

   “The air bags light does not come on meaning the module is not functioning. I had the car inspected and it failed due to this issue. Records show a recall was registered in 05. Well here it is 10 years later and the problem was not resolved and something overlooked. It's a safety hazard regarding my life and others as well not knowing if these air bags deploy or not while I'm on the road. I need this resolved quickly. They never fixed the problem the first time so why's it happening again?”

   NHTSA complaint #10682316, filed 2015-02, 64,000 miles

   “While driving on a rainy day at 50 MPH, the driver applied the brakes to slow down the speed, however the consumer lost control of the vehicle and was involved in a head on collision. Upon impact, both air bag didn't deploy. The consumer was traveling on the highway when she heard a hit under the vehicle, then lost control.”

   NHTSA complaint #10062976, filed 2004-04, 150 miles
3. 3
   Engine cooling

   Engine stalls, overheats or shuts off while driving

   • 11 complaints (6%)
   • median 55,556 mi at 4.1 yrs old (10 state mileage)
   • 1 mention a crash, fire or injury
   • filed 2004–2013

   Owners report the engine quitting at speed or at a stop, sometimes restarting only after being left to sit, and in other cases overheating with coolant loss followed by a breakdown. Several describe repeat overheating after a dealer repair, coolant leaking out, and a check engine light coming on shortly after pickup. One complaint describes a hole in the engine block with a large oil spill after an oil pressure warning. Mostly reported between about 50,000 and 90,000 miles, with a few cases at very low mileage.

   2 related service bulletins

   What to check: Check coolant level and condition, look for residue around hoses and the thermostat housing, and ask whether the coolant temperature sensor or crankshaft position sensor has been replaced. Have a mechanic scan for stored codes.

   2 excerpts from owner complaints in NHTSA records

   “I was driving on the highway and suddenly the oil light came on. At the same time, there was a loud noise so I pulled over and turned off my car. Minutes later I tried to turn it on but no life whatsoever. Got out of car and saw big oil spill along the side up to where I drove to. Drove car to mechanic. Engine had hole in the engine block.”

   NHTSA complaint #10495085, filed 2013-01, 67,050 miles

   “(1) can happen anytime without warning. May go for weeks, days, or minutes before recurring. (2)engine shuts off while driving. Must shift into neutral to restart. Not easy to do when doing 65 MPH on rt 30, to suddenly have no power or power steering and a semi is on your tail. It has happened at least 20 times since the first time in wet, dry, fast slow, or idle. (3) 1st time wiggle wires. It would not happen in the shop. Replaced fuse box, we refuse to drive the car again due to fear for our lives. …”

   NHTSA complaint #10139860, filed 2005-10, 4,000 miles
4. 4
   Vehicle speed control

   Engine speed rises without the accelerator pressed

   • 8 complaints (4%)
   • median 56,000 mi at 6.8 yrs old (6 state mileage, few)
   • filed 2004–2018

   Complaints describe the engine revving on its own in park, neutral, drive or reverse, with the car creeping forward or backward despite firm brake pressure and the tachometer climbing. Owners say the condition is intermittent, that cleaning the throttle body helped only briefly, and that turning the car off and restarting sometimes cleared it. One report ties a related cruise control episode to brake lights going out. Reported from around 15,000 to 90,000 miles, in both low-speed parking situations and highway driving.

   What to check: During a test drive, let the car idle in gear with the brake held and watch the tachometer for wandering, and check that cruise control disengages on the brake pedal. A throttle body cleaning and inspection record is worth asking about.

   2 excerpts from owner complaints in NHTSA records

   “Sudden acceleration incident I am the son of the car owner. I was driving the car. The incident occurred about 8:30 am on june 17, 2010, in bethesda, md. I was exiting the giant food parking lot and stopped for traffic along old georgetown road. The car stopped but then all of a sudden inched ahead. I pushed down harder on the brake; heard the engine racing; saw the tachometer go past 6000 rpms. I immediately put the transmission in neutral. The engine was still racing. I turned off the car. …”

   NHTSA complaint #10339241, filed 2010-06, 32,060 miles

   “My vehicle revs on it's own. Starting and stopping through town is very dangerous because it is difficult to stop the vehicle. As I hold the brake down the car continues to accelerate as if my foot is on the accelerator. The car revs in park, neutral, drive, and reverse. I took it to a local mechanic. He cleaned out the fuel throttle and the problem went away for about 1 week and came back. I talked to another mechanic and he had never heard anything like it. He told me it was probably a defect.”

   NHTSA complaint #10346870, filed 2010-08, 85,500 miles

Buying note. On this model year, the priority check is the front passenger air bag indicator with a real adult in the seat, along with proof that the OCS recalls were done, since that is what most complaints describe. Also budget for a cooling system and sensor inspection, and test the belts and throttle behavior on the test drive.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.