pntbllfun

I am working on my 1999 2.8 engine

i am trying to get the downpipes off of the exhaust manifold. The (what seems to be 3) bolts are facing the rear of the car and i cant figure out what tool to use to get at them. I have access to a huge selection of tools from my buddys garage but i cant easily just grab em and try things out because my car is in my garage

I dont really have alot of room from the underside, but i have everything except the actual heads out from the top of the engine so there is a decently clear path. does anybody know how exactly to get those bolts off.

jschick

these come very easily once you find the correct path!!! YOU NEED TO BE FLEXIBLE. If you search my posts you can find some detailed descriptions on how to reach them, but I will try from memory, I believe they are 13mm, the passanger side, 1 bolt you reach from up top, 1 you reach from thru the fender well and one from underneath the car, I use a 1/4 inch ratchet with a 13mm socket. and a box end wrench for the one up top (the O2 sensor is in the way so you can't get a socket on it). the drivers side I am pretty sure all bolts can be reached from under the car, but one may be easier from up top. remove the coolant bottle and you can feel the one top bolt. if you are pulling the heads don't remove the manifolds just these bolts!! I have done several of these and so far never ran into one that would not come right off once you found the path! but a good 1/4 ratchet works well in the small space, if you don't have one then a 3/8 will work but it will just take a little longer since you can't get the movement with the bigger tools

mrfixit54

Thanks to this post by jschick I was encouraged and able to do what appeared to be the impossible...replace the passenger side cat pipe on my 1999 A6 Avant 2.8L. My car is fitted with three nuts on studs at the header connection. All 13mm wrench size, with air intake tubing removed I was able to get a combination wrench on that top nut. I also alternated this wrench with a longer box-end wrench; that nut will come off! As for the two other nuts located at about 9:00 and 3:00 o'clock positions, as jschick mentioned, these require a 1/4" ratchet and 13mm socket. I gained access to these two nuts by removing the RF wheel then "hugging" the RF hub. With bright light I was able to see and get those two nuts removed. I unplugged the forward O2 sensor then disconnected that once the cat pipe was removed. I installed the Bosal pipe and a new gasket and was very pleased with the fit and quality of this product. Thanks again to jschick for without his post and encouraging words I could not have done this crazy job.

06SilverA3

Hi guys, I know this is an old thread, but I'm hoping someone has a trick or technique for reattaching the exhaust pipes to the manifolds, and you guys have obviously been there. I had the engine out of my '99 A6 2.8L 30V V6 to fix a coolant leak in the rear main flange, inside the bellhousing. I have the motor bolted back up and torqued down, but have spent a day trying to get the exhaust pipes bolted back on. The angle seems all off and I can't even get a nut started to pull it back on, either side. I've tried all sorts of leverage and pulling with ropes to try to align them, to no avail. Seems like it should be easier and therefore I'm missing something obvious.

Here's a pic of how far I got. Any suggestions are very welcome.

mrfixit54

I have done this on my 1999 A6 Avant. I hope that my two cents may be of some help, if not at least encouraging.

I found that the driver side is way easier than the passenger side. There is quite a bit of room to work up there.

As for the passenger side...I had to replace or at least remove that down-pipe. (make sure your O2 sensors are good before bolting these pipes down...to do that later on the passenger side is impossible) It has been a while so I forget which it was; my records would tell me. When looking up there at those very difficult-to-see nuts I said this is is impossible! It turned out that with the R-F caliper/rotor covered with a blanket I was able hug that caliper and had visual/physical access to one or two nuts. The third nut... I was able to reach from more underneath the suspension.

I would be happy to look at my records in order to say exactly the size and style of wrenches that allow for success...just let me know. My 1999, with 250,000 miles required a replacement transmission, which I did have done...that was a miracle! Having maintained that car for many years was quite time consuming. I just could not spend any more time, or money on the best car ever. I was lucky to find a buyer who was thrilled to have a car that looked, handled, and ran so well. I am now enjoying a VW Alltrack...more than you needed to know.

Good luck.

06SilverA3

@mrfixit54 Thank you for the encouraging words. Mine is also a '99 A6 Avant Quattro with 140K miles. I've been working on engine coolant leaks for the last year (see my other post) and am in the home stretch. The mileage you had when you finally parted with it gives me hope for mine and whether this ordeal is worth it (my wife is a definite "no" to that question).

I'm good with getting access and have an array of 13mm sockets and knuckle joints to bolt them back on (I too have embraced the passenger wheel hub to remove the exhaust and that infernal starter motor bolt). I simply can't get the flange onto the studs to bolt them back to the manifolds. Did you raise the pipe with a floor jack, or tie it up or something, or did yours just line up and slip on? Did you have someone else assist in getting it lined up? I can't figure out how to get the studs through their flange holes and a nut started on either side.

This is what mine looked like before I tore the whole front end off chasing the leaks.




Thanks again for the help.

mrfixit54

I recall using 13mm sockets with 1/4" drive. Maybe 13mm box end too.

For myself, I never had troubles getting the flange to engage the studs. I worked alone. I recall too that I may have tried many different angles to get that pipe flange in place.

I looked at your pics on the site...wow! God bless you! I never did my own timing belts services...too spooky for me to take the time to learn.

Your car looks really nice and well worth fixing. They were beautifully styled, and truly great cars...just need lots of maintenance.

I wish I could be of more help to you.

You have many great guys helping with your questions...these men helped me too with my service questions.

One day my heater hose broke. I kept filling the system and limped it home. Not sure why but my trans went into limp mode after replacing both heater hoses next to the battery. I had a local shop try to fix the limp mode but the trans never shifted right again...the car just could no longer be driven.

Be sure to replace those two hoses next to the battery. I also replaced all coolant hoses, surely you are planning that as well.

I used 10W-30 Lubrication Engineers Monolec oil in that engine. Changing every 5,000 miles. The engine used about a quart of oil every 2000 mile but never smoked.

Keep those spark plugs tight...I had one blow out on me! How it ever loosened I will never know...I put a timesert in the RF cylinder.

06SilverA3

Well, finally got the exhausts bolted back on. I didn't attempt removing the pipes because they're welded together in several places and thought I'd get in deeper trouble if I took the whole thing off to try to align the headers. It only took 7 hours! I raised the exhaust downstream from the motor with a small floor jack and that helped me get the driver's side on the studs and bolted down, but the passenger's side was all askew and jammed up against the manifold in the wrong position. After hours of trying to push, pull, lever and coax the damned thing I ended up loosening the driver's side again, but leaving just enough thread in the nuts to keep it attached but loose (really didn't want to start over with that side) and then after giving the whole system a good shake I got enough slack in the passenger side to allow me get a couple of levers to pry and pull it into position. I can tell you I did a little happy-dance when it finally popped onto the studs. Now it's all bolted down and tight.

Excuse the bad pic, but here's the floor jack lifting the exhaust system up.


Here's how bad the passenger side was misaligned when I had the driver's side bolted up.


Thanks again for all the help with this one