Hi, did you ever get to the bottom of this? I just got a P0404 this morning and am pottering along at 20 miles an hour! I have ongoing carbon build up issues that manifest themselves in various ways. I had my EGR replaced a couple weeks ago so not that, Its going into my Saab specialist in a couple of days but just curious what your solution was (I suspect mine will be big and expensive )

 

Notwithstanding the first post in this thread, which is nearly a year old, but to vman, do you know when your vehicle last carried out a DPF regen?

I had my own car dealer serviced yesterday, usual Tech 2 hook up included and no problems shown on my TID engine. Technician did tell me though that he's had to carry out some forced regens (well, Tech 2 controlled regens) to sort owners issues out when initially the EGR was believed to be the problem. It could be that all your engine needs is a total DPF scream out on a forced regen, indeed, the DPF could be saturated or in need of replacement (how old is the car/mileage)? Your ongoing issue with carbon build up could be just the fact the engine isn't getting the runs it needs. I'm lucky, I live right next to a motorway, the car gets a good thrashing occasionally! Certainly (and I don't know what useage your car gets) but city or town only driving is, from research, not much good for the modern diesel engine. I'm assuming, the reason why Saab released a software update in February 2012 specifically to force earlier regens for cars that are used for mainly for town or city driving, was to help counteract some of the issues.

I'm sure someone on the forum will be able to elaborate further or debunk what I've posted!

 

vman also remove and clean the egr pipe going from side of egr valve to the inlet manifold as this will be blocked
i have done a how to on this and what you need available in the how to section

 

Yup it's in the how to guys! We've all been there and done that! Well clean the EGR that is...

 

I got my spare EGR valve this morning ( thanks for the tip Virtualm!) - I'm going to swop it for my recently cleaned valve and see if I notice any differences. After the last thorough clean of the existing ( 105k miles) valve which included separating the 2 halves I thought there was a definite improvement in smoothness and power delivery in the 1-1.5k rpm range. No1 requirement for the EGR system is that it must be able to shut off all EGR flow as fast as possible when you want any power delivery from the engine so the valve has to be able to snap shut instantly and any gunk buildup on the valve seal or stem is going to be a problem.