Small noise from under the hood - United Bimmer Community

**///Mman721** · 07-11-2006, 12:58 AM

I (and alex) did an oil change on my car around early June, and we noticed a small grinding/rattling noise which seemed like it was coming from the very front of the engine---i don't remember hearing it before the oil change---all the internals in my engine are new (on a side note this probably was the reason why I beat harry when I raced his dinan ///M also). Many have suggested that I shouldn't worry about it that much, and that it may go away. I didn't worry about it until today while washing my car I became double curious about it, fearing it could be bad. I have only driven the car about a thousand miles since then, the noise hasn't gotten louder or anything. I have asked a regular mechanic who is a friend of the family (non-bmw mechanic) and thinks it may be because I switched synthetic oils (previous owner used something else, I went to 10w-40). He said switching to a different grade may make it go away. He also said I may need my valves adjusted possibly. I'm taking the car to a trusty bmw mechanic tommorow morning to find out exactly what it is. Any ideas gentlemen? Fire away.

**Dudesky** · 07-11-2006, 04:53 AM

Your description is a little vague, so it's hard to make any serious guess. But your mechanic's theory is plausible. Or it could be something simpler, like a timing chain tensioner or one of the pulleys up front

**///Mman721** · 07-11-2006, 08:58 AM

Yeah my description is vague because the noise itsself is weird, I can't hardly tell where its coming from--im mostly sure its coming from the very front of the engine where the timing chain is, and if you put your hand on top of it, it feels like that part has something grinding inside of it. But there is no power loss performance wise, just that noise....

**c1apton** · 07-11-2006, 05:38 PM

When all the "internals" were replaced, did you replace timing chain tensioner? I suspect a chain doing a little slap in the timing cover via your description.

**Chris** · 07-11-2006, 08:48 PM

^^^^
Nice Theory!

Clapton is the BMW Demigod.

**///M Power** · 07-12-2006, 11:49 AM

Quote:

Originally Posted by c1apton

When all the "internals" were replaced, did you replace timing chain tensioner? I suspect a chain doing a little slap in the timing cover via your description.

Ditto. This is a common problem.

**///Mman721** · 07-12-2006, 12:46 PM

Yeah, I think C1apton is right. I think that's what it is. But I took it to a bmw mechanic, and he's confident its the dreaded V word (vanos) system making the noise. He claims also that the system is kinda noisy anyways, but I think definetly not like this. I'm taking it to a few more mechanics today, but I guess I won't be 100 percent sure until its opened up and checked out.

**///M Power** · 07-12-2006, 04:03 PM

You just need ot have him take off te cover adn tighten up that chain.