Hi - For 2005 Octavia 1.9Tdi (later shape model) can any one advise on what to replace for fault code P0401. Main dealer said they can drill down with their testing capability and identify the part that needs replacing. With testing and part it would be in the region of £170. Does anyone konow if that fault code is specific to a single part or several?

If the part is fitted does the fault code turn off or does it have to be reset so the engine management light goes off?

Thanks for your help.

I am almost certain that is the code for an EGR fault......

Could mean it's blocked, or damaged. If you are mechanically minded you could remove it and check - although iirc the 1.9 is at the back of the engine against the bulkhead. I have a EGR delete pipe fitted to my 2.0 PD140 and it activated a CEL, I had it mapped out when I remapped the car, but the dealer or possibly someone with VCDS locally could turn off the light.

By the way what mileage has your car done?

I am almost certain that is the code for an EGR fault......

Could mean it's blocked, or damaged. If you are mechanically minded you could remove it and check - although iirc the 1.9 is at the back of the engine against the bulkhead. I have a EGR delete pipe fitted to my 2.0 PD140 and it activated a CEL, I had it mapped out when I remapped the car, but the dealer or possibly someone with VCDS locally could turn off the light.

By the way what mileage has your car done?

Hi, thanks for your reply mine has done 75,000 miles and is on variable servicing. I did disconnent the hose from the throtle valve and have a look at the EGR valve as best i could. From what i could see it was not heavily laden with oily residue. Thanks Rob

Try this site for a complete explanation: Ross-Tech Wiki

An EGR valve is about a ton and I would suggest (IMHO) 170 fitted is about right. However, if the EGR is blocked the inlet manifold might be too. http://www.myturbodiesel.com/1000q/a5/clean-intake-manifold-PD.htm

Might be worth asking what they propose to do about that?

edit: fix URL

Edited 1 February, 201214 yr by FriendlyFire

Hi thanks for your advice and for providing the links. Regards

Rob

From ross-tech wiki

16785/P0401/001025 - Exhaust Gas Recirculation (EGR) System: Insufficient Flow Detected

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) Flow restricted/clogged

Exhaust Gas Recirculation (EGR) Valve stuck closed/leaking/faulty

Wiring and/or Connector(s) from/to Exhaust Gas Recirculation (EGR) Valve faulty

Exhaust Gas Recirculation (EGR) System 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

From ross-tech wiki

16785/P0401/001025 - Exhaust Gas Recirculation (EGR) System: Insufficient Flow Detected

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) Flow restricted/clogged

Exhaust Gas Recirculation (EGR) Valve stuck closed/leaking/faulty

Wiring and/or Connector(s) from/to Exhaust Gas Recirculation (EGR) Valve faulty

Exhaust Gas Recirculation (EGR) System 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