I have a A6 2.7T Sport with Triptronic. At the far ends of the steering radius under hard acceleration I get an odd 'clunck' noise. I get no noise at any other point in the steering nor do I get the noise until I hit the gas HARD. I only notice it because I have a hard turn at an intersection that merges into traffic on my way home each night. I took a 2.8 Avant out and tried the same turn and I thought I heard something similar, but the car is not in that great condition and being heavier and slower it was hard to make a comparison. So, has anyone else noticed this? Is it normal at the far ends of the system?
Next, I am having some wierd intake issues. On cold mornings the car chokes unless I rev it up a little first. If I don't, it will be "surgy"/lethargic for the first 30 seconds or so. It only does it when I start moving, not when I rev it. Then, if I didn't rev it up a little the check engine light will turn on at the EXACT SAME PLACE. The code reads as a bank 1 sensor 1 O2 sensor AND the secondary air pump. In the afternoon, the check engine light will turn off. I'll go for a couple of days and then it will be cold again and it'll all happen again. Related to this (at least in my mind), is that when I'm going down hill in cruise control I can feel a tiny surge/slow. When the car shifts the RPMs kind of slide, almost like the clutch was slipping.
My gut feeling is that all of this is being caused by a loss of boost pressure due to the OEM diverters, but I would like to try and confirm symptoms with you guys. My plan is to put an APR bipipe kit and either forge or bailey diverters on.
I sometimes notice a similar sound from my car on hard turns also. I just contributed it to the limited slip diff making some noise on hard turns. Don't know for sure, but I have had experience with other cars making some noise out of the diffs on hard turns.
As far as the other problem, I just had mine in for service over the secondary air injection not having enough flow (check engine light). It turned out to be a leaking vaccum line on the combi valve on the #2 bank. I have heard these valves collect alot of carbon and can be troublesome about throwing codes.
Again... I am by no means an expert but atleast it is a starting point.
well for the clunking noise on hard turns, it could be a strut that is blown out. i kno on my other car, a 2000 honda accord, when i go over some hard bumps and corner fast it clunks
the clunking noise you heard is probably your diff or something connected to it... My friends WRX does the exact same thing!!!! he has still yet to fix it or confirm what it is... But that is our guess.
Posts: 57
Joined: 4/29/2004 From: United States Status: offline
If you turn the wheels to the lock and accelerate hard from stop or slow speed on just about any car with front drive axles, you risk making noise as the outer CV joint tries to turn at the sharp angle you've fed it. The manufacturers ususally set the steering bump stops a little sharper that they might like for CV health so the customer has a turn radius less than a city bus. I've managed to make mine clunk a time or two.
Posts: 17
Joined: 3/19/2004 From: United States Status: offline
strongly recommend you flush, with hyd fluid your hyd system, with front on jacks and cycle steering stop to stop, drain/empty and repeat. Hyd system needs clean non contam fluid or it will mes everything up which gets $$$$$$. The steering rack is very prone to dirty contam fluid. Man reccommends every 2 years do it yearly. Every Audi I have owned 1978 Fox, 87 TQ5K, 95 100, 2001 2.7T have done this with. Always drained and replaced hyd fluid racks and barkes lasted over 250K on each. expect 2.7 only 70K so far.
Advise you get a VAG COM hook up your lap top and check the faults and O2 sensors, we have 6 at aver $100 each this gets pricey. VAGCOM and fault codes make doit yourself repairs MUCHO easier. remember our cars run on computer and sensor inputs these sensors are important and get effected bad connections and exhaust contaminates. I doubt it is your surge valves your turbos do not work much at start up. But stock valves are cheap check eBay. The way your treatin this now you will do more damage on start up by reving a cold engine. It will last longer like our body parts if it is warmed up first. Good luck
Funny thing, i brought my car into the shop yesterday for these same 2 items, as well as a few others. The guy aty the desk asked what kind of gas i use, since i use 93, he said in colder weather use reg, or a lower premium, nonetheless they are checking it out. I should recieve word by noon and i will update this post then..
_____________________________
Current: 2004 A8L
Gone 2001 A6 2.7T Apr Tuned 93 OCT ECU 605 relay mod ;} 710N DV's
Golt my car back, they said it was a loose shield or guard, the sputter they said is from the higher oct in the cold, checked it out fully, they said, well at least i have it on record.
_____________________________
Current: 2004 A8L
Gone 2001 A6 2.7T Apr Tuned 93 OCT ECU 605 relay mod ;} 710N DV's
Printable Version
Two 2.7T problems + questions... - 
