2000 A4 1.8T 155K miles - The daily driver that will soon have an exhaust....and chip.
I got a leaky exhaust flex pipe last Friday. I figured the rest is gonna go sometime anyways, so Iordered up a Borla 14845 cat back (delivered last night) and picked up the gasket at the dealer this morning. I did a 3 inch cat-back on a friend's EagleTalon AWD about 5or 6 years ago,andit took all of 30 minutes. I'm experienced at doing this kind of stuff.
But this A4 has got 3 rustednuts/bolts that are a PITA to reach by any means. I hit uptherusted threads with some liquidwrenchthis afternoon after work. I got2of the heat sheilds out of the way so far,and still have a tough time getting a grip on the bolts at the back end of the cat.
Has anyone here done this themselves before? Is there something else that has to come out, or some other way of doing this.
I have tried to get at the bolts with 2 feet worth of 3/8 drive extensions and socket. The size is 13mm on the bolt/nut, is this correct?
Is the attachment hardware a nut and bolt, or a bolt with a nut welded to the flange, or a stud welded to the flange with a nut on the other end...?
It's rusted so it's hard to tell.
I don't plan on replacing the cat yet, so i don't want to mess stuff up to much.
Any advice from anyone who has done this would be appreciated.
Thanx,
Bogie

 

haha yeah, you gotta get some pb blaster. soak the bolts for a few hours and then have at it. its still gona take forever tho. to get to the cat/dp bolts you gotta get a long extension and then put a flex joint at the end of it. then miraculously fit it onto the socket and come up with a way to produce enough torque to get those suckers loose. took me about 3 hours just on those bolts. good luck and just have patience. (or you could just saw right through downpipe and make it easier on yourself)

 

All that's left of the stock downpipe is the foot long piece and stainless steel flex tube-it would have fallen completely off at some point this week if i didn't loop up a trusty coat hanger from the tail cone of the trans to the pipe in back of the flex joint.
So you sure nothing else can/should come out to make this easier. I got to pick up an extra 6" extension piece and a 3/8 breaker bar in the morning. Did you get them out from above or from below? Thanks?

 

you cant get them from above. its gotta be done from below. the nuts are welded onto the cat, so you gotta go at it from the bolt. but yeah there's no secret trick. i couldn't get the really long extension onto the nut so i had to put a little flex joint on the end. the extension runs into a bend in the pipe, so its gota be done at an angle. if you had airtools it would be a breeze

 

I got airtools, but didn't even think of it. Dopey dooo. Did you reuse the old bolts?

 

u have air tools and didn't even think of using them? ahhhhhhhh i would kill for air tools lol. i wouldn't resue bolts like that if i were u lol.

 

yeah, well it wouldn't have helped if i used an air ratchet to try to loosen a nut that is welded to the cat. U know the size/thread of the bolts? I'll need to get them in the morning at the dealer before the parts counter closes. Home Depot doesn't have S#!T in stock for metricbolts.

 

call the dealership. they're comp tells them evrything. and if they say their comps don't say, they are lying. been there, done that. and ay home depot sux with their screws and bolts. is there a lowe's by u? the one by me has 2 huge tool boxes that are all full of metric bolts and nuts. the dealership will rape u evn for bolts man. been there and done that too. just wake up early and shop around. u'll save at least 10 bux

 

Thanks, i gotta find the size first. Dealership is a 1/2 mile away (could bike there) and lowes is 25 minutes - not worth my time to go there by comparison if i don't have to. i picked up 3/8 and 5/16 bolts today, but i bet when i finally get them out they will be metric and i can get my $10 back that i spent at home depot earlier today. (on the 12V w/ nitrous - i didn't mean to reply to you- i mean it to reply to oneg- i work w/ the guy who's son has that car - he was talking about the NOS at lunch one day this week.) let's see a 2.8 with nos vs a 1.8T quattro with exhaust and chip to come...i think i'll win.

 

well u mean his 12v vs ur chipped 1.8t u'll win. it'd be a good race if u were up to my 30v though. u'd prolly still win cuz ma car is running like crap right now. and i doubt the bolts u got will work lol. and ya they are def metric. evrything on our car is metric. the dealership should be able to tell u the specs and then u'll be on ur way.