EGR Valves.

[Old Peter]

A problem with EGR valves came to S Type 2.7D recently.  I corrected ir using an additive which did not last very long and the AA  Engineer using an OBD2  found that it was one of the EGR Valves required cleaning.

I referred this to my regular mechanic who took my car awayto fix it.  He rang back about three hours later telling me that "The catalyst was blocked causing back pressure which he had regenerated."  EGR valve amber light gone and the engine was working correctly.

This sounds quite easily done and £50 was on the invoice.  

BUT there was a recommendation —  The system needed a deep carbon clean.  The exhaust was 15 years old [a for life sates steel exhaust] can still get some carbon inside.

Diesel catalyst deep clean — an 8 hour job was the answer and the result was a total cure. —  Price for two mechanics - £200.

My s type with 88.008 miles on the clock has now given me the smoothest drive and the best acceleration  I have had in the 9 years I have had the car.

Cleaning the exhaust should last 15 tears.  [I hope I last that many years!] 

[Wrinkly]

Peter

Interesting post here.

I have a 2005 2.5 V6 Petrol Automatic which is constantly throwing Fault Code P0420 (Catalyst System Efficiency Below Threshold0 Bank 1. I have numerous posts on this Forum about this fault but despite many good people giving suggestions and advice we have still not got to the root of the problem. Do you think this cure of your problem could/would help my petrol engine S Type. Do you know what the process of a "Deep Catalyst" clean was. 

Many thanks and Best Wishes, Regards, John

[Old Peter]

Hi John,

A deep clean of catalyst appears to be using a system of cleaning out the exhaust all the way up to the valves.  It appears that there are several experts with the correct fluid to put in and run the exhaust for an hour or two.

That is just what the novice [I am only 87] gets to know.  But it worked!  My car is a diesel[

When I next see my mechanic I will find out more.

Regards,

Peter.

[Wrinkly]

Peter

Many thanks for making the effort to ask for me.

Regards, John