Loud Rattling Noise at Start Up
 

Hello everyone!

Does anybody know what is making this noise whenever I start the car? The rattling goes on for a couple of seconds after starting. If I turn the car off and quickly start it up again, the noise doesn't happen. However, if I wait even 5 minutes after turning it off, the noise comes back when I go to start it again.

Someone told me its pre-detonation (knock) because of poor fuel. Not sure if that is the case.

Thank you!

[ame]http://www.youtube.com/watch?v=Dffoe78k14Q[/ame]

Holy shit that sounds terrible.

If it was bad fuel why would the sound go away like that?

Because the computer senses the knock and adjusts the engine parameters for the lower octane fuel.

I'm not an expert so hopefully someone can chime in. I would think the knock wouldn't disappear shortly after start (since the fuel quality isn't changing).

Would it have something to do with injectors? Doesn't the fa20 start on direct then switch to the port? Again I might be mistaken (more than likely I am) so hopefully someone more knowledgeable will have an answer.

I agree with you. I also thought knocking had a different sound than this. Not sure about the injectors but this happens when the engine is cold and when it is warmed up as well.

That sounds ugly. Definitely something I would want a dealer to look at. The sound seems to go away as the engine builds some oil pressure...cant really tell from the video, but it is likely either valvetrain related, or (gulp) the bottom end. Get it to a dealer. Just an opinion...others may vary.

Go to the dealership. There is nothing normal about those sounds. It sounds like the Pistons are rubbing on the cylinder walls. Terrible sounds are coming from your engine.

Good luck the dealership should make it right.

Damn that doesn't sound good. That is definitely not from bad gas. Have you checked your oil level lately?

Sounds like shit, when's the last time you changed your oil?

I'm gonna go out on a limb. A/C compressor? Disengages after fault detect? No CELs?

No CELs. AC works fine.

About 4 months ago (I go by months since I don't drive enough for the mileage count). I was actually planning on changing it today since I do it about every 4 months so I'll see if this somehow fixes the problem. Oil level has been good.

Yes, I regularly check it and it has been good throughout the 4 months since I last changed my oil. I'm planning on changing it today though.

You seem to be right about the built up oil pressure because if I turn the car off and immediately turn it on, the sound doesn't happen. But if I wait a minute and then turn it on, the sound happens. I do plan on taking to the dealer now, it sounds like a serious problem.