A5 3.0 TDi EGR


New Member
Sep 28, 2021
Reaction score
I was having a problem with my A5 engine light coming on so I went to the Audi dealer and he said the problem is the EGR . He quoted me a fortune to fix it . Reading these Forums I saw that Remapping the engine would delete the problem plus gain performance. I had that done and I am very happy with the result. However my tuner mentioned that water could be in the EGR and this could give me some issues later on. Could this be correct and what might the issues be ? Would thid stillentail the major operation that the Audi dealer quoted me on or is it a simple fix if it is indeed a problem. Regards Champcarman.
The EGR itself is water cooled, so yes, your tuner is technically correct. Did the tuner mention why he thinks water might be in the EGR?
No , could it be connected to the original fault causing the engine light to come on? Would it be a major operation to get the water out ?
It could potentially be connected to the original fault, which caused the EML to come on. Taking the EGR out requires the upper intake to come out, and in some cases the lower intake due to how snug the fitment is. It's a time consuming job more than anything, and steps must be taken to make sure that the fuel pump is primed properly post assembly via software (except CAPA engines), as well as the water feed being correctly plumbed back into the cooling system. As for "removing water", it wont be sat around and will go wherever the air pushes it. The default position of the EGR is closed, but it isn't a water tight seal, so if there is water in there, it'll either be going into the air intake (unless there's a blanking plate), or back into the exhaust system via suction.

Also, depending on what the tuner has done, you may get a fault code once the EGR has been removed. If the remap included an EGR delete via software, then there shouldn't be any issues in that regard.
Thank you Vappy for taking the time to reply, most appreciated. One more question though (sorry to be a nuisance), if I do nothing about it can it cause damage to my engine (short term or long term) ? By the way this is my first Audi (a 2010 A5 S line Sportback) and I really love the car. It has 180000 kms on it but runs beautifully and I have had it for about 7 months now and have been changing the oil about every 5000s kms.
I'm glad you're enjoying it mate. They're great cars and great engines, and can go on for a long time if serviced and cared for properly. It's best to have it sorted now rather than later - water in an area where air usually resides is a no no, because water beats piston every time. If it gets bad, it'll either go straight into your air intake and cause catastrophic failure while starting/running, or if there's a blanking plate between the EGR and the upper air intake, it'll fill up gradually within the EGR and leak upstream somewhere/go into the exhaust system.

You either replace the EGR with a new one and not have to worry about it again, or you ask someone with the knowledge and experience to remove it entirely, blank off the EGR cooler and upper air intake where the EGR used to connect to with a metal plate, and then route the previously used coolant line to the EGR back into the cooling system. Both will take time and money. The former solution is easier than the latter, but you are paying for a part to be fitted that is potentially not being used by the car's software anymore due to the remap.

All the best mate

Similar threads