2004 Hyundai Sonata Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 2004 Hyundai Sonata
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2004 Hyundai Sonata ProblemsNoise on Startup Due to Failing Timing Chain Tensioner
If you experience excessive engine noise on startup (after the engine has been turned off for several hours) that lasts for more than five or six seconds, turn off the engine and check that the engine oil level is correct. If the oil level is correct, the noise may be caused by the timing chain tensioner. Hyundai has an improved tensioner to correct this problem.
On the 2.7L V6 and 2.4L 4 Cylinder, a defective exhaust gas recirculation (EGR) switching valve may cause an intermittent rough or unstable idle engine.
If the automatic transmission does not shift properly and the Check Engine Light illuminates, the speed sensors in the transmission may have failed. The sensors are simple and inexpensive to replace.
2004 Hyundai Sonata Questionsbrake light won't turn off (1 answer)
This was my reading when it went through Emissions.
Monitors Not Ready:
MIL Remains lit at key-on-engine-running
MIL Commanded On
1 Trouble Code Reported:
P0056 HO2S Heater Circuit Bank 2 Sensor 2
When I start the car from a cold start the ABS & Hand Brake Light goes off. After a warm start the ABS & Hand brake light stays on.