I live in Madison, Wisconsin, and this winter got pretty cold. On one particular morning I noticed that my '06 Sonata V6 GLS (60k) was making a slight diesel sound when idling (not too obvious), but when I hit the accelerator the diesel sound was more prominent. A few weeks later, it got down to well below 10º F and the car actually had a slight issue starting and then the check engine light came on. I called my mechanic and he was booked so he couldn't check it that day. Next day, check engine light was off, but ever since then the diesel sound is there when I get up and take off for work in the morning.

The warranty just, and I mean just, expired before this all started happening (bought it used). The noise will only start if it sits over night, or for more than 4-6 hours in below freezing temps, and it only lasts for about 30 seconds. Apart from that sound, no performance issues when the engine is warmed up. I don't ever jam on the accelerator when it's that cold out. I'm just wondering what it's doing to the engine. I don't need any major future issues. I want to know what I can do know. I did finally get it into my mechanic and he said that it was hard to tell what's wrong without the check engine light on. He didn't seem to think anything was wrong. And normally, he's pretty good with things. Although I think he's better with American cars, than Japanese or Korean.

Any ideas? I'm afraid to take to Hyundai because honestly I don't trust many dealerships. I used to work at the local Kia dealership.

Thanks all!

 

Early 3.3 liter V6 engines were manufactured with faulty timing chain tensioners. The symptoms you describe are consistent with that problem. Here are two links to TSBs describing the problem, the last one being the most important:

http://www.hmaservice.com/files/331/.../06-20-002.pdf

http://www.hmaservice.com/files/331/...M-001-1pdf.pdf

You need to read these and then discuss the matter with your local Hyundai service manager. I have heard of instances where Hyundai did repair the problem as a warranty fix after the warranty had expired.

Good luck.

 

Thanks ken99. I'll post what happens.

 

Very good. Here is another link for you to read:

http://www.hyundai-forums.com/t34271...006-sonata.htm

While I have heard some Hyundai dealers will extend the warranty to repair this problem for no or minimal cost, I should warn you I have also heard of some dealership doing everything they can to avoid dealing with this problem. The repair requires extensive dismantling of the engine, and some dealers do not wish to tie up a service bay for one or more days on a warranty repair. This repair can be handled by any Hyundai dealer, not the one you may have purchased the car from. If you are not happy with the first dealer you talk, you can move on to another.