Hello, I would be very grateful if someone could give me some advice.

I recently bought a 2015 Audi A3 Cabrio Ambition 1.6 TDI clean diesel 110 CV 6 speed .

Soon I noticed that the engine light was on. This is on permanently. Then occasionally the flashing glow plug comes on, usually after 30 minutes of motorway driving. This glowplug light clears if the ignition is restarted. I did an OBD scan and got:

P040200 — Excessive flow in the EGR system

P010100 — Mass Air Flow (MAF) sensor, range/performance

P047100 — Exhaust pressure sensor, range/performance

I put the car in to an Audi main dealership, and they replaced the battery, and cleared the faults, but the faults returned immediately.

I then went to an independent dealership where they wanted to immediately remove the DPF which seemed excessive with no diagnostic evidence to justify it.

As far as I understand, things like the EGR can be tested without dismantling by commanding them to act and reading the physical responses and gases. I was hoping that a garage would do tests like this to actually diagnose the fault before taking physical action and replacing items.

I am looking for advice regarding what the likely cause could be, and also, what action I should take, and what I should ask the next garage to do.

Many thanks!

10 hours ago, alanmm said:

Hello, I would be very grateful if someone could give me some advice.

I recently bought a 2015 Audi A3 Cabrio Ambition 1.6 TDI clean diesel 110 CV 6 speed .

Soon I noticed that the engine light was on. This is on permanently. Then occasionally the flashing glow plug comes on, usually after 30 minutes of motorway driving. This glowplug light clears if the ignition is restarted. I did an OBD scan and got:

P040200 — Excessive flow in the EGR system

P010100 — Mass Air Flow (MAF) sensor, range/performance

P047100 — Exhaust pressure sensor, range/performance

I put the car in to an Audi main dealership, and they replaced the battery, and cleared the faults, but the faults returned immediately.

I then went to an independent dealership where they wanted to immediately remove the DPF which seemed excessive with no diagnostic evidence to justify it.

As far as I understand, things like the EGR can be tested without dismantling by commanding them to act and reading the physical responses and gases. I was hoping that a garage would do tests like this to actually diagnose the fault before taking physical action and replacing items.

I am looking for advice regarding what the likely cause could be, and also, what action I should take, and what I should ask the next garage to do.

Many thanks!

Hi if the Maf is knackered it will affect the EGR which is probably stuck open, you can start by replacing the Maf and Map sensors as these share information and if one has gone the other is not far behind, both components affect the engines ability to regenerate the DPF, if the EGR is stuck open this will fill the DPF in record time therefore strangling the emissions system, if the car has done a fair few miles allied to the age of the car these problems often occur, replacement is the only real option.

Steve.

thanks, its off to the garage tomorrow, I will include these suggestions