[Masher]

Anyone have any idea what bolt this might be? I've looked around nothing seems close. Its pretty large... about the size of my thumb.

Found it in my engine bay last year... haven't noticed anything wrong since then though.

[Daaaaaaaan]

Post a pic of the opposite side. Does a heavy duty (like a speaker or hard-drive) magnet attract it? What's the size of the bolt head?

Did you find it in the belly pan or elsewhere? Could've been kicked up by another car if it looks like it could fit through one of the grilles.

[TheMidnightNarwhal]

Definitely looks similar to the O2 plugs that comes with modified downpipes like the VRSFs I have.

Yeah like above did you find in belly pan? Is it that short or looks snapped?

[Buug959]

It is a fill or drain plug. It doesn't appear long enough to actually fasten anything. Is there any sort of gasket or o-ring on the underside of the flange?
This is the plug that came with my VRSF downpipes. It doesn't have the same kind of flange or the thread locker compound.

[Daaaaaaaan]

Originally Posted by Buug959

It doesn't appear long enough to actually fasten anything.

OP's bolt is different. OP's has an integrated washer, but yours does not. Maybe that's what you mean by flange? OP, does the washer come off the bolt (might need to hammer it off as it might be held by corrosion) or is it 1 single piece?

That's why we want OP to take a picture of the bottom, so we can see if it was sheared off, or if it was that length from the factory.

OP needs to provide a lot more info. Could be road debris for all we know.

[TheMidnightNarwhal]

Originally Posted by Buug959

It is a fill or drain plug. It doesn't appear long enough to actually fasten anything. Is there any sort of gasket or o-ring on the underside of the flange?
This is the plug that came with my VRSF downpipes. It doesn't have the same kind of flange or the thread locker compound.

I think the older VRSFs downpipes came with a plug that looked like OP's with the washer, as my plug was like OP's IIRC.

This listing has the pic with a plug bolt with washer but it's hard to tell image isn't high res.

https://detailingconnect.com/product...-bmw-335i-135i

[Masher]

Originally Posted by Daaaaaaaan

OP's bolt is different. OP's has an integrated washer, but yours does not. Maybe that's what you mean by flange? OP, does the washer come off the bolt (might need to hammer it off as it might be held by corrosion) or is it 1 single piece?

That's why we want OP to take a picture of the bottom, so we can see if it was sheared off, or if it was that length from the factory.

OP needs to provide a lot more info. Could be road debris for all we know.

Here's a pic for the backside of the bolt.

There's no washer it's part of the bolt, it was found in the engine bay on the side, must have been left there?

Originally Posted by TheMidnightNarwhal

I think the older VRSFs downpipes came with a plug that looked like OP's with the washer, as my plug was like OP's IIRC.

This listing has the pic with a plug bolt with washer but it's hard to tell image isn't high res.

https://detailingconnect.com/product...-bmw-335i-135i

It could be from downpipes like in the pic actually. The o2 sensors are pretty large.
Prolly not a drain plug since the bottom is clean? No o-ring found.

Bought downpipes at n54tuning 6+ yearss ago, unbranded but prolly vrsf tbh. So that lines up with it being the older vrsf that had this. There is hope

[Buug959]

Originally Posted by Masher

Here's a pic for the backside of the bolt.

There's no washer it's part of the bolt, it was found in the engine bay on the side, must have been left there?




It could be from downpipes like in the pic actually. The o2 sensors are pretty large.
Prolly not a drain plug since the bottom is clean? No o-ring found.

Bought downpipes at n54tuning 6+ yearss ago, unbranded but prolly vrsf tbh. So that lines up with it being the older vrsf that had this. There is hope

If you had downpipes installed the mechanic probably dropped the plug when he was installing the O2 sensors you're just discovering it now. I wouldn't worry about it.

[Bmw1939]

That is the main power train bolt. It holds everything together Your car is ruined now. I'll give you 3k for it. Lol.

It looks like a fill bolt and looks very old. Maybe a tech dropped it under at the dealer and elected to just replace it rather than fish for it.

[Brian86]

Looks like the timing chain cover cam sprocket screw access hole plugs on S/M 50/52s