So I did my timing belt/valve covers along with all seals water pump ect ect.
Also did cam adjuster friction plates. Oh yeah and all crank vent hoses and vacuum tubing.
Everything went fine but when i was done I had one small bolt and one small nut left over!! It's been driving me nuts figuring out what i could have missed.
This is my first A4 so it's new to me. I NEVER had left over nuts/bolts when working on my mk1/mk2/mk3 vw's since i know them so well. And if i did i would know where they went.
Any old schooler audi heads who could possibly identify it?
oh yeah it's a 2.8 5v engine.

 

What size is the bolt? Is it the front driver side bolt on the ignition coil pack? It bolts in, then there's a ground or some sort of wire that sits on top of the bolt, then the other nut goes on top of that. This is the only thing that comes to mind that you may have taken off when doing the TB service..

 

i did indeed remove the coil pack while working on the car.
I will go out and check to see if its from that.
this extra bolt/nut is driving me nuts! the car drives awesome now.
what a difference new crank case breather hoses and fresh sparkplugs make!

 

I think Ian is right - did a cam chain tensioner a couple weeks ago and I remember that stack bolt. Front driver side corner of the valve cover, there are two bolt holes close together. One is for the cover itself, and one secures a couple parts in a stack.

 

nope.. checked both spots. nothing missing. still at a loss. i even went through etka trying to find the bolt in the diagrams!

 

I recently did a TB and motor mount job on my '02 S4. I also have a leftover bolt (M6x20) that I can't find a home for. I can't find any good leads in ETKA either. There are actually (according to ETKA) not that many M6x20 hex head bolts in the S4, and I think I've found most of them. Others aren't even close to where I was working or I can't decipher where ETKA is telling me to look. I've pretty much given up. In the process I've done the TB job 3 times to make sure it wasn't in any of those parts. The water pump uses 9 M6x20's and all are accounted for. The crank plug bolt is another and that is in place. Arghh!! I notice in you pic that we don't have the same leftover bolt. Good luck in your search. My bolt has consumed me for weeks.

 

Just chalk it up as weight reduction

 

My problem will be when the thing it's holding down decides to remove itself for weight reduction. I hope it's a majorly redundant bolt where ever it goes.

The car is all together now. Three timing belt remove-installs in a few weeks is all I can handle. I have heard some rattling somewhere in there, but I almost need to start in 3rd gear to shake the engine enough to bring it out. I can hear some mid-high pitched metal on light metal vibrations. Although, I did bend the heat shield on the pass. side a little getting the air box in maybe that's the rattle. I just want to drive it before winter.