Hi on my 2007 Hyundai Sonata limited with a 3.3L v6 engine with 285200 miles. Only on cold starts it rattles for 2-3 seconds then goes away. It doesn't do it after those seconds. When engine warm or hot it doesn't rattle just on cold starts . Was wondering what could be wrong?
Can you make a YouTube video & post the link here?
No, motor is not blown. It is a loud rattle . Its hard to explain. Engine runs beautiful nothing wrong just rattles
If it's similar to InThurstWeTrust's video link, that's a timing chain rattle. Upon starting, especially a cold start, it takes a few seconds for the oil to move out of the pan to fill the filter. From the filter it goes to, at the end of this relubrication journey to the timing chain tensioner. So, for a few seconds, there's no oil to lubricate the timing chain or its tensioner. Especially for an engine with this many miles on it, a brief rattle is normal, except when a filter check valve is defective (more common with cheaper filters). Those can rattle with every startup, warm or cold.
You could change the filter. Otherwise, the sound is normal for an engine with some age on it, such as this 14 year old Hyundai.
- Is it something to really worry about. With that many miles. I dont want anything bad to happen. I want the motor to last a long time . It only does it on cold starts and engine runs great. I keep up with oil changes every 2 to 3thousand miles.
Sometimes it doesn't even rattle
It doesn't hurt to run an OBD2 scan, particularly with enhanced diagnostics, to get an overall picture of the health of this vehicle. But, THE SOUND IS NORMAL FOR AN ENGINE OF ITS AGE.
The timing chain almost always lasts the life of the engine. More to the point, how much oil is the vehicle burning between oil changes? That's a more significant variable in assessing engine life.
And, yes, BTW! 285K! You've done a great job maintaining the engine.
I ran the scanner the only thing that came up was Cadillac converter . It has an oil leak. One quart every 3000miles the valve covers are leaking i use castrol gtx ultra-clean 5w-20 synthetic oil
What is the timing chain doing to cause that rattle ? Do you know about how long can it last with its making that rattle problem?
The catalytic converter is an expensive item. It could be that it's running just below peak efficiency. Scotty has videos on using either soap and water or pouring in lacquer thinner to clean a catalytic converter running below efficiency.
Depending on where you live (because of different pollution testing rules), you may or may not fail "a smog test" next time you go on.
Changing a valve cover gasket isn't that hard. You'll find videos online demonstrating how to go about it. Don't be surprised if your spark plugs are oily, and need to be changed out.
Then, after that's been changed, you'll have a better idea how much oil your vehicle is burning.
I changed the spark plugs and coil packs recently.
You could change the spark plugs and coil packs, but if the vehicle has a leaky valve cover gasket, the oil will leak back onto both the coils and the plugs. If this was done at a shop, and the valve cover gasket was leaking, it was incumbent on them to point that out, so that the replacement plugs and coils would not be fouled by oil.
What is the timing chain doing to cause that rattle ? Do you know about how long can it last with its making that rattle problem?
If enhanced diagnostics show that the engine is running normally, then, why worry about that? But losing all that oil from the valve cover gasket is a problem, because of the damage to spark plugs, coils, and eventually, running the engine with less than optimal oil level. And, of course, that's supposed to be a sealed environment. Leaks allow contamination of the cylinders and the engine, as well.
I understand. But i always keep the oil level on full at all times
Which means that there's all that much more oil fouling up other components. If you're handy at all, with a few tools and a replacement valve cover gasket, you can end all that leaking and clean up the immediate environment. It's better for the cylinders, the spark plugs, the engine, etc.
Fundamentally, the timing chain is stretched from millions of rotations. It may also be that the timing chain tensioner is a bit loose. At 286K, these are not unexpected events. It has a lot of time underneath its belt, so to speak.
Okay. I really appreciate it. I just want to make sure of what the problem was.
If its the timing chain, will it break? Or it’s uncommon for it to do that? If it does what happens?
Generally, these last the life on the vehicle.. The tensioner may need adjustment. You'd have to inspect to know more. Frankly, at 285k, I'd be conservative on any major engine work.
Okay thank you