I have a 2006 Sonata V6. It is now making a noise like a Diesel engine when the temp is below 32 deg F. It does this for about 5 minutes until engine warms up. Like a lifter or something is sticking? Any thoughts? It is loud like a Diesel.
Rhanck

 

Do you have a Hyundai oil filter on it or a different brand? What weight oil is in the engine?

 

Many, if not most, of the 2006 3.3 liter V6 engines were constructed with defective timing chain tensioners. The sound is a severe rattling in the engine at startup and dimishes as the engine warms up. The cold weather must make it sound worse. Hyundai has recall on these engines for full warrenty replcement of the tensioners. Take the car to a dealership.

http://jerrystout.us/sonata/tsb/timi...eplacement.pdf

 

I nowtook my Sonata to the dealership. They told me the noise is normal ????? They said it is the hyrdrolic lifters when it is cold and I will notice it more when it is colder.

I have had this car for 2 years and not had this noise. It is a loud rattle or knocking sound for the first few minutes. VERY BAD NOISE. I do not understand that this noise is normal. My 2007 Santa Fe has the same engine and it doesn not make this noise.

Not sure what to do now. Maybe trade it in for a Toyota Camry.

I am wondering if it realy is the timing chain tensioner and the dealer does not want to deal with fixing it. I think I should try another dealership. Any other thoughts guys. Thanks

Rhanck

 

You might want to try a different dealer or ask them to start up one of their new V6 Sonatas to see if it makes the same noise. If they say it is normal the new car should sound the same.