B6 Passat 2006 1.9 BXE P0401 code?

[Practical Goat]

Hi guys,


I've had a reoccurring fault code that keeps coming back after 20 miles. P0401 which says egr insufficient flow. I've removed the EGR valve to see if it was stuck, it was partially gunked up but I've seen worse. I cleaned it any how and cleared the code. It's back


I've checked the vacuum pipe from the valve to the main vacuum block and no splits. I've heard it could be the MAF, the cooler, the valve itself and I've even heard someone mention the turbo. I have vcds so if anyone requires any readings to help me out I would be very grateful.


Thanks.

[Doctle Odd]

Ross-Tech Wiki

[MarkTM]

I had a similar issue on my Audi A6 3.0

001025 - EGR System
P0401 - 002 - Insufficient Flow - Intermittent
Freeze Frame:
Fault Status: 00110010
Fault Priority: 0
Fault Frequency: 2
Reset counter: 255
Mileage: 168910 km
Time Indication: 0
Date: 2014.09.25
Time: 12:51:15

In my case it was the cast ali pipe between the TB and intake manifold, off that pipe are two nostrils that lead to the EGR, removed and used oven cleaner from 99p shop and a power washer. Dried and replaced and no return of the issue.

Good luck!

[Practical Goat]

I've done all that. Still no cigar.

[Practical Goat]

Thanks Mark, I'm hoping to get some parameters so I can narrow down any dicky readings.

[MarkTM]

pics can be seen here

TB Cleaning Photos

Basically crud accumulates around anywhere near & in the EGR you just have to clean it all out