Hi,
Got a 2000 A6 2.7T Biturbo. (UK)
On long run to London ECU came on. Had laptop with so ran VAGCOM and got misfire and it indicated cylinders 4,5,6.
16684 - Random/Multiple Cylinder Misfire Detected P0300 - 35-00 - -
16688 - Shareware Version. To Decode all DTCs P0304 - 35-00 - Please Register/Activate
16690 - Shareware Version. To Decode all DTCs P0306 - 35-00 - Please Register/Activate
16689 - Cylinder 5 Misfire Detected P0305 - 35-00 - -


She was running rough on idle but ran fine on motorway so drove back.
Got home and did the amp swap over test suggested elsewhere. Cleared the DTCs and ran the engine for a while. Showed misfire on 4 & 5 again.
My assumption then was not the amp but the coil packs.
If my research is right 4,5 & 6 are down one side.
Two questions basically:

1. Other threads stating 4,5 &6 on drivers side, but I am assuming that is for left hand drive vehicles, so 4,5 & 6 are on passenger side on UK (right hand drive) car?

2. I am going to replace the coils on 4, 5 & 6 (and all the plugs while I am at it). Is this a sensible first move?

Many thanks in advance

Cheers
Danny

 

Most of the time when the misfires are on one whole back it's the O2's & EGT that are the cause.

One test is to swap the coil packs to the other banks & see if the misfires follow.

 

many things cause this and the codes dont help im going for the coolant temp sensor even though no code for it was registered and all because its one side of the v6 giving the problem, it could also be the cam sensor or MAF so check all the pipes are tight and no holes or splits

 

Thanks for the responses.
I've had some time now to do some checks etc.
So far have replaced the plugs and coil packs (all of them)
The MAF and Coolant sensor are new and less than 4 months old (Coolant sensor is the green one not black)
I stripped down all the air intake system and checked for leaks, tears etc.
New air filter whilst I was down there
Replaced and used new clips everywhere.
(Also I had already tried swapping the amps over and fault stayed with 4,5 & 6)

Started her up, cleared the codes and ran for a while.
Engine still showing misfires on 4, 5 & 6

What I don't understand is why say the O2 or Temp sensor would only give misfires on one side.

With regards to the EGT suggestion, do I take it there are 2 on the 2.7T with one for each bank.
Is it worth changing these even though no VAG codes coming up.
Can they cause misfires on one set of cylinders.

Any help greatly appreciated as my shaking Audi is doing my head in

Cheers
Danny

 

worth a read these guys seem to put it down to upstream O2 sensor that's the one after the cat ( passenger side UK )

http://tech.bentleypublishers.com/th...threadID=14011

EGT could be a cause because of exhaust gas temp incorrect reading but could also be down to O2 sensor sending bad signal to the EGT because they are linked

 

CEL Light on again.
Now getting
P0300 / P0301 / P0302 / P0303 / P0304 / P0305 / P0306 & P0431

As a recap I have replaced all plugs and coils and checked for air leaks.

Reading as much as I can from the forums I get varying ideas around
1. Changing the CAT
2. The upstream O2
3. The downstream O2

As I am getting just a P0431 , but all six cyl misfires now, am I back to a vacuum leak theory, or should I look to change the O2 sensors and if so how many of them as not a cheap option at the moment having forked out on a batter, two track rod ends, coils etc

Some advice and guidance on possible vacuum leak locations, or indeed if the O2s are to blame would be very welcomes

Cheers
Danny

 

Hi

Saga continues. However due to my mother being in hospital and daily trips there and back have had to leave CEL light on and put up with constant misfire and 14mpg.
However got VAGCOM on just now and whilst still got
P0300 / P0301 / P0302 / P0303 / P0304 / P0305 / P0306

but the P0431 has disappeared.

So again a plea for some guidance, as to what to try next
O2's etc etc

Thanks in advance
Danny

 

Just did one with similar symptoms at the shop recently......was showing misfires on 4 and 5......Turned out the timing belt had jumped a tooth and was causing it to run really bad at idle but almost undetectable at higher RPMS. When was the timing belt replaced or has it even been replaced? Also, try cleaning the MAF sensor, could be that as well.

 

If you have time please read the original thread, as I have lived with the CEL light for over a year and no adverse affect on the car apart from annoyance factor.
I still get basically P0300, P0304, P0305 and P0306
I think I've got some enthusiasm worked up again to try and fix, but still not a great idea of what to try first.
I still have varying thoughts on
O2 sensors
Crank sensor
EGT sensor
Vacuum leak
But to try all these costs.
Was wondering if any fresh ideas considering no other codes are showing a year later and the car runs fine. It may be slighly rough on idle but to be honest it may have always been like that.
Thanks in advance

 

HI,
Similar situation here.. 2000 s4 tip car. 101k on the clock, Misfire on #5, Changed the pack, no change, Cleaned the plug, No change, Cleared the code, no change! I am the general Manager of a large Chrysler Jeep Dodge store! But I love my european cars period so I drive them still. I owned a store for 7 years and then sold. If any body will help me through this I will promise you need a true wholsale value on a car of some market reports as to what the cars are doing in the auction feel free to ask. I know you have better things to do than hold my hand but this sucks. The damn car runs rough and its as fast as a fricking ford festiva!! LOL!! WTF!! So its gonna be my daily driver and it needs to be what it is should be! I have a wrench at the store that is pretty savey with them. He owns VW'S and what not. Where should he go first or should I just roll into Audi and take it in the ***!!! Its shows a random misfire code. This happens a lot from what I see. I have unplugged the MAF and no change in the way it runs.