407 2.0ltr hdi - pugeot - m@

hi
I asked you a question last week to which you replied that I should debate/haggle /come to agreement on price due to dealerships inability to diagnose problem!
the saga continues!
after being verbally guaranteed last week by the workshop engineer that if I have the EGR valve replaced at a cost of £400 that would definitely be the problem resolved!
I told them that I could only just afford this work so it MUST be the end of the issue!
they did the work,replaced the EGR valve and rang me to say collect car, then just as my wife got to the dealership they rang again to say there was a further problem but they didn't know what it was?
TODAY,5 days later I get a call saying I need to replace the DPF system at a further cost of £600
I don't know what to do now?
I took my car to the garage,three times they said they knew the problem and could fix it three times I have paid for this and I am now still in the same position as when I first went to them, except for I now have a car that doesn't drive safely but it does have quite a lot of new bits on it!!!!!
please can you advise me again on how I should approach them,should I ask to discuss it only with the manager of Hawkins@st.stephens cornwall where this fiasco has occurred?
I really don't feel that I should have to pay for all of this inconvenience!
I don't want to 'pay under protest' I want my car fixed for the original agreed price they gave me AFTER running " full diagnostics checks......please, who do I report this crap to??
thankyou for your time and I apologise for the angry tone of this message,I am simply at the end of my tether!

407 2.0ltr hdi - pugeot - Peter.N.

This is quite a common practise but I don't know how they get away with it. I was a TV engineer for 50 years and if it wasn't right when I took it back it was down to me to repair it.

I know its a bit late now but you are better off going to a diesel specialist than the dealer, they usually know what they are doing and are generally cheaper.