Engine making a weird rattling sound.

So I got up today and got ready to drive my car to school, but when I started it up I noticed this weird rattling sound. Its not much louder than a loud valve tick, like if you're late on changing your oil. It persisted even after I let the car warm up and it gets louder when I rev the engine.

I remember having a similar sound just one other time shortly after changing the oil but it went away in like 5 seconds. This one is sticking around.

Theres no CEL and no weird smoke (just a couple white puffs on startup but thats normal). I'm worried that it might be something serious so I'm not driving the car until I know what it is. Any thoughts?

Sounds like it might be a spun bearing.

Drain the oil through (including what is in the oil filter) through papertowels or something. Copper flakes/chunks are from your bearings.

oh god i hope not. if it helps it almost sounds kindof tinny. I was thinking it might just be as simple as a belt rubbing up against something after the accident I had but I hadn't noticed it before and something like that should be heard right after the accident.

I dont have time to do anything with the oil right now because I'm about to go to work but would copper flecks show up on the dipstick if it was a spun bearing?

wouldn't I notice anything when driving the car if it was a spun bearing?

Another method is to use something completely metal like a wrench or something. Put one end to the bottom of the block, and one to your ear and use it as a stethscope if it is obvious it is in the bottom end it is probably a bearing.

If/when you have the chance to do these, if it appears to be a bearing, pull the pan and make sure.

As far as knowing about it while driving. I've havn't had it personally happen, so I can only say what I've heard from others. You'll be picking up alot of knock, which I would assume the ECU would retard timing (loss in performance) as a result. Also you should see a loss in oil pressure...however, being that our stock gauges are crap, you may not even notice it :dunno: Oil light may come on.

I seriously would get it towed, and not drive it. I mean look at it this way, if you drive it and it is a spun bearing you are now getting that oil filled with metal shavings going through your turbos. Also if by some miracle your crank is still ok, it wont be for long.

Also, I forgot to mention this. As you said before it is quieter than expected and it might just be a belt. This is possible. I had a friend who thought he'd spun a bearing in his car, it turned out a bolt came loose from his alternator or something and the bolt or the alternator or something was making similar noises. So don't jump to conclusions and worry yet....but be ont he safe side and don't drive it either.

Very well could be what Geoff mentioned. Sounds exactly what happend to my car. Otherwise it could be some other bolt coming loose as mentioned. I once had a loud rattling sound in my car and a bolt on the flywheel came off, but it did sound serious.

have you listened around the engine bay to try and locate it? I had a similar experience with my car like a week after i brought it home. turned out to be the heat shield on the rear turbo hittling a bolt or something on the firewall. Its a quick enough check, so you might as well.

like Igo, ive never spun a bearing so i dont know exactly what it sounds like, but what you describe at "tinny" sounds a whole lot like what mine was.

I agree with others, you may have a spun bearing, it happened to me last year. But it could be a belt, which i had happen to me last month. Definately check your power steering belt and hope to god its something like that and not a spun bearing. If it is a bearing you can drive it, but like Igovert said, you will be getting the metal in your turbos. I drove mine for a good month with a spun bearing but i didnt have to worry about turbos, although it really got loud and rough above 2000 rpm.

I'm gonna do what I can before going to work today but again, I dont have much time. Hopefully I can get some time with the car on saturday morning before I go to work when I dont have school.

actually now that I got down into the engine and listened with a wrench, when I put it up against the transmission (the closest available metal thing to the sound) it almost sounds like a scraping, but it comes and goes with a couple seconds between. I guess I wont know whats what until i drive it tho.

Drop the oil and stab a hole in the filter and drain it all through a paper towel first. Driving it is rarely the answer.

well the sound just went away... so i don't know what to think. i drove it and it was fine even up to redline. i guess i'll just have to see if it comes back later.

Maybe it was simply a loose screw that finally rattled itself loose adn out the bottom :dunno:

your guess is as good as mine. hell for all I know, my car has self repairing nanites that fixed the problem lol

Thats good to hear, i bet you were really nervous there for a while. Just hope it doesnt come back!