You-think-it's-not-there-but-it's-there kind of clunk

[Mr Paddle.Shift]

I just realized today that there is a clunk whenever I accelerate from stop. Fact is it's a very faint clunk coming from almost below my driver's floor. Sometimes it's there, sometimes not. It wasn't apparent until today. I am going to the dealer this week to get some trim replaced so I will bring up the issue.

I have to confess two things:

1. I did drop a screw while working in my car a long while back. It was an attempt to clean the air-conditioning grilles that I left a screw on the dash. Worst thing was I saw it rolled off SLOWLY towards the wind screen and happily dropped into the ventilation drain. :(

2. Got one of those magnetic interchangeable drive bit? You know one of those one tool many uses crap? Well, I have that. Most of the SCTS members saw it before. While using a hex bit to remove the ECU cover, the bit decided to take a break from me, and dropped beneath the ECU box well. Never found it.

So what are the chances that the clunk might be one of these? :(

[clyde]

IME, screws, bits, sockets, etc that disappear in situations like that make "clank" noises as opposed to "clunk" noises. In fact, they usually create a rattle or buzz at certain road or engine speeds as they vibrate against whatever is restraining them. "Clunks" particularly those that are heard only when starting, stopping, running over things have usually been loose attachments that are moving from end of their play to the other.

:dunno:

[SpaceMonk]

Right. I don't think either problem you mentioned would constitute a "clunk" either.

I've also recently discovered a loud clunking noise when I downshift into 2nd or 3rd at high RPMs only. It can't be the synchros, since I'm double-clutching, but if I'm accelerating hard and downshift into the lower gear at 5-6000 rpms, I hear a really loud clunk. :(

[The HACK]

It's your guibo on the tranny side. Check and see if there's cracks in it. Clunk will only get worse now that you have a few more hamsters under the hood.

If it IS the guibo, have them replace it with E46 M3 guibos, they're suppose to be much stronger. Although Stuka did manage to tear through his in less than 30K miles.

[Mr Paddle.Shift]

Thanks for the replies guys. Hamster still in cage. So can't be him in the car. :D

Now that Clyde mentioned clank, it does sound like a clank. The words clunk, clank, creak and squeak all sound possibly to me now. I have to drive again tonight to see.

Hack, not to doubt you at all, but what's a guibo? Sounds like something from Gilligan's Island. :paranoid:

EDIT:

Ok, did a seach on guibo. And yup it does sound like that's the problem. Check out Rogue Engineering's link (http://www.rogueengineering.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=RE&Category_Code=GUIBO).

Hack, thanks for the note. You da man!

[The HACK]

My plan is to get the M3 guibo when I put in, um, the next upgrade. :paranoid:

You will need the new guibo AND new set of bolts. Those bolts are one use only...Unless you get some lock-tite.

[Mr Paddle.Shift]

Hack,

I just spoke to Imad and he's quite positive that the fuel filter might be faulty. Or the FPR could be faulty since the M54 models have the FPR integrated into the filter. Samir has expressed the same concerns as well.

Either way, I have now three places to get my car checked into: dealer, EMW and Renn-sport. I will come back with more results.

[The HACK]

Hack,

I just spoke to Imad and he's quite positive that the fuel filter might be faulty. Or the FPR could be faulty since the M54 models have the FPR integrated into the filter. Samir has expressed the same concerns as well.

Either way, I have now three places to get my car checked into: dealer, EMW and Renn-sport. I will come back with more results.

Imad thinks that the fuel filter is faulty and that's what's causing the problem? Well, it IS in the right area (right underneath the driver's door), but given how many miles you have I doubt it's the filter. They're good for about 60,000 miles.

Unfortunately I have the old style filter so I'll never have to experience that crap. I still put my money on the guibo, but let Imad take a look. Or we'll take a look next time at a TS or something. If it's the FPR then I'd think you would have drivability problems, no?

Another way to test...Put your car in neutral, pull up on the hand brake, and lightly accelerate to duplicate said "clunk". If clunk present, then it's the FPR/Fuel filter like Imad predicted. If it doesn't, then it's likely the guibo.

[Mr Paddle.Shift]

Update:

Guess what? It's a dangling (or almost) transmission line. Renn-sport tech, Zolti, tightened it back and everything is fine now. Strange. I replicated the noise this morning and we suspected that the engine rubber mounts might be bad. Anyway guibo fine, mounts fine, everything fine.

Oh and....the ASA SC system in perfect working order. :D