Hello everybody!
I've got a BRE engined 2007 Audi A4 Avant CVT 2.0 TDI which I bought just under a year ago. About a month ago it's started developing a misfire which reliably occurs in certain conditions. I can't find a post from anybody with a similar issue so I'm a little lost on this...
When started from cold, it runs absolutely fine, it always starts on more or less the first crank, then will run as normal for the entire duration of the 'engine cycle?' ie. from when it starts to when it's switched off. It will have no issue getting up to temperature, and driving ok at temperature. If I start it from cold and drive to say the shop down the road, giving it no time to really get warm, turn it off, then start it back up and drive wherever, it'll be ok too.
However, once it's warm and it's started again, it'll run fine for about 5 or 10 seconds, the engine will then start violently shaking since it's misfiring, or at least feels like that. It'll shake at idle and when accelerating or cruising below around 2500rpm, if I drive above that, around 3000rpm, it'll smooth out, and accelerating above 2500rpm is fine. Once I switch it off and on again it'll start misfiring again after about 5 seconds.
On occasion, I've been able to stop and start it again and it's reverted to running like normal, but this is say a 1 in 5 or lower chance, and again it'll run absolutely fine on that engine cycle until it's switched off and restarted.
The engine warning light is on, but it's been on since I bought the car due to some glow plug circuit fault, but because it's always started spot on I never looked deeper into that. I ran a fault code reader I borrowed (Ancel VD700) on it a couple of weeks ago and it came up with the following codes:
P0266 - Generic - Cylinder 2 Contribution / Balance
P0674 - Generic - Cylinder 4 Glow Plug Circuit / Open
P126300 Cylinder 2 pump / injector valve implausable signal
P030200 Cylnder 2 Misfire Detected
From the reading that I've done trying to find a solution to this issue most people, including my friend who has a garage locally recommend is to replace the injector wiring loom, which makes sense, but the symptoms are slightly different in their case as they find it misfires as it warms up instead of between ignition cycles. I'd like to find out exactly what the problem is before I start replacing things.
On this particular car the EGR valve has been removed and most likely mapped out by a previous owner.
Any help would be appreciated as this is really driving me mad, most of my journeys at the moment are pretty short, if I'm driving locally it dosen't give me much problem but there are points in the near future I'll need to venture further.
Cheers!
Aled
I've got a BRE engined 2007 Audi A4 Avant CVT 2.0 TDI which I bought just under a year ago. About a month ago it's started developing a misfire which reliably occurs in certain conditions. I can't find a post from anybody with a similar issue so I'm a little lost on this...
When started from cold, it runs absolutely fine, it always starts on more or less the first crank, then will run as normal for the entire duration of the 'engine cycle?' ie. from when it starts to when it's switched off. It will have no issue getting up to temperature, and driving ok at temperature. If I start it from cold and drive to say the shop down the road, giving it no time to really get warm, turn it off, then start it back up and drive wherever, it'll be ok too.
However, once it's warm and it's started again, it'll run fine for about 5 or 10 seconds, the engine will then start violently shaking since it's misfiring, or at least feels like that. It'll shake at idle and when accelerating or cruising below around 2500rpm, if I drive above that, around 3000rpm, it'll smooth out, and accelerating above 2500rpm is fine. Once I switch it off and on again it'll start misfiring again after about 5 seconds.
On occasion, I've been able to stop and start it again and it's reverted to running like normal, but this is say a 1 in 5 or lower chance, and again it'll run absolutely fine on that engine cycle until it's switched off and restarted.
The engine warning light is on, but it's been on since I bought the car due to some glow plug circuit fault, but because it's always started spot on I never looked deeper into that. I ran a fault code reader I borrowed (Ancel VD700) on it a couple of weeks ago and it came up with the following codes:
P0266 - Generic - Cylinder 2 Contribution / Balance
P0674 - Generic - Cylinder 4 Glow Plug Circuit / Open
P126300 Cylinder 2 pump / injector valve implausable signal
P030200 Cylnder 2 Misfire Detected
From the reading that I've done trying to find a solution to this issue most people, including my friend who has a garage locally recommend is to replace the injector wiring loom, which makes sense, but the symptoms are slightly different in their case as they find it misfires as it warms up instead of between ignition cycles. I'd like to find out exactly what the problem is before I start replacing things.
On this particular car the EGR valve has been removed and most likely mapped out by a previous owner.
Any help would be appreciated as this is really driving me mad, most of my journeys at the moment are pretty short, if I'm driving locally it dosen't give me much problem but there are points in the near future I'll need to venture further.
Cheers!
Aled
