Audi A6 ERG problems

[Meggy4241]

Hi guys, this is my 1st post so be gentle on me.

Im having major problems with my 2015 Audi A6 Avant 2.0Td1 Ultra Sline. over 2 weeks ago it broke down on the motorway. Glow plug light flashing and Engine management light on and black smoke coming out the back. Car shut down and wouldnt start again.

I had the car recovered and the recovery driver advised taking to a mechanic friend of his who was supposed to have experience in these issues. Got to garage and Mechanic reckoned, after plugging it into his computer that it was EGR that needed replaced so i left the car with him. 2 days later he rang and advised that he was going to remove the EGR and DPF and have them professionally cleaned. He said there are 3 DPFs in my car. He did that and also replaced a heater plug and a boost sensor. Finally after 2 weeks with my car he got the car going again and the car driving ok but the glow plug light was still flashing. He plugged it in again to the computer and it was showing an undocumented code. So we took the car to AUDI who did a full diagnostic for £60. Initially they found no fault (Audi think the mechanic wiped the codes before i took it to audi) but when i picked the car up from Audi the flashing glow plug light came on, so i took it straight back and they plugged it in. Only thing they could find was a P04020 code "EGR Flow Excessive detected" (see attached pic). Audi said they would need to remove the EGR at a charge of £495 just to tell me what is wrong with it. They also said it could cost a further £1800 to fix. I contacted the mechanic and gave him P0402 code and he said its the motor on the EGR and says it needs replaced with a new one and wants to charge me a further £630 on top of the £1300 for his previous work. Im not happy that he didnt replace the EGR initially. So i have drove the car home to make a decision. The car drove home fine apart from having the flashing glowplug light on and orange engine management light (not flashing). Also Start / stop function showing a fault when the car starts but this fault/ warning light goes away after a couple of seconds.

Obviously the mechanic did not resolve the issue by removing the EGR and DPFs and having them cleaned.

Any advise would be more than welcome. Should i get the entire EGR replaced including the EGR cooler. Could it be one of many Sensors. eg DPFE Sensor. Could the mechanic have put the cleaned EGR back in using the old gaskets ? Does the brain of the car need told that a new or cleaned EGR has been put back in ? Also ive read this could all be related to the audi emissions scandal. Any thoughts

I am exceptionally reluctant to drive the car. Some have suggested having the EGR and DPF removed and Mapped out but that could cause problems in the future regarding MOT testing at the MOT centres here in Belfast.

Ive attached 2 pics the mechanic sent me before they were cleaned.

Thanks so Much MEGGY 4241

[TheRenegade]

I've been posting in another thread about my EGR. It wasn't a good idea for the first mechanic to just clear the codes like that if you ask me. He should have at least saved them if he was going to wipe them. According to the Ross Tech website, the EGR needs a damn good clean. See below.

16786/P0402/001026 - Exhaust Gas Recirculation (EGR): Excessive Flow


Possible Symptoms
Malfunction Indicator Light (MIL) ON
Reduced Exhaust Gas Recirculation (EGR)
Reduced Power Output/Engine running rough
Increased Emissions


Possible Causes
Exhaust Gas Recirculation (EGR) Valve stuck open/leaking/faulty
Exhaust Gas Recirculation (EGR) System leaking/faulty
Wiring and/or Connector(s) from/to Exhaust Gas Recirculation (EGR) Valve faulty


Possible Solutions
Check/Clean Exhaust Gas Recirculation (EGR) System
Check/Replace Exhaust Gas Recirculation (EGR) Valve
Check Wiring and/or Connector(s) from/to Exhaust Gas Recirculation (EGR) Valve

[philipharmes]

The DPF won't be able to do a regen while this code is present, so is slowly filling up with soot again.
So it need sorting ASAP.

What is the engine code ?