+ Reply to Thread
Page 2 of 2 FirstFirst 1 2
Results 11 to 20 of 20
  1. #11
    Join Date
    Sep 2016
    Location
    Burnley
    Posts
    533

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    At that point the catalyst temperature sensor will stop working and they are not cheap.

    You can understand why so many people remove the DPF and disable it, one of the worst ever over complicated bags of rubbish fitted to cars.

  2. #12
    Join Date
    Jun 2005
    Location
    Aberdeenshire
    Posts
    2,010

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    78 plus VAT from Mercedes last time I checked DPF temperature sensor prices.

  3. #13
    Join Date
    Jun 2005
    Location
    Aberdeenshire
    Posts
    2,010

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    Have now figured out the workings of the differential pressure sensor. It is a Wheatstone Bridge type. The membrane has two fixed resistors at the outer non stressed part of membrane. Two resistors span membrane and get stressed when membrane is exposed to pressure. Reason for having the fixed resistors on membrane is to ensure their temperature is same as the two stressed resistors as otherwise changes in fluid temperature would cause errors in pressure read out.

  4. #14
    Join Date
    Sep 2016
    Location
    Burnley
    Posts
    533

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    Like I said, over complicated bag of rubbish. They all work (or more often don't work) like that.

  5. #15
    Join Date
    Jun 2005
    Location
    Aberdeenshire
    Posts
    2,010

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    Of course all passenger car diesels regardless of make made from 2007 have diesel particulate filters, sensors and controls including all the associated trouble that make them unreliable and expensive to run.

  6. #16
    Join Date
    Jun 2005
    Location
    M5 junction 4
    Posts
    471

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    No DPF nonsense in my 2009 45hp cdi
    2009 Passion Coupe Cdi - RHD
    Previously;
    2007 Passion Coupe - RHD
    2000 Pure City Coupe - LHD
    2001 Pulse City Coupe - LHD
    2003 Passion City Coupe - RHD
    2000 Passion City Coupe Cdi - LHD

  7. #17
    Join Date
    Jun 2005
    Location
    Aberdeenshire
    Posts
    2,010

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    Quote Originally Posted by tolsen123 View Post
    Have now figured out the workings of the differential pressure sensor. It is a Wheatstone Bridge type. The membrane has two fixed resistors at the outer non stressed part of membrane. Two resistors span membrane and get stressed when membrane is exposed to pressure. Reason for having the fixed resistors on membrane is to ensure their temperature is same as the two stressed resistors as otherwise changes in fluid temperature would cause errors in pressure read out.
    Bosch video showing how the pressure sensor works:



    The faulty sensor indicated constant negative pressure and negative voltage about - 0.4 V. Applying vacuum to its downstream DPF port made sensor pop and spring back to life. Can only conclude the membrane was stuck to the chamber wall where positive pressure is nomally applied. Perhaps too little clearance on that side of membrane since it is supposed to flex the other way.
    Last edited by tolsen123; 29th September 2018 at 15:31.

  8. #18
    Join Date
    Sep 2016
    Location
    Burnley
    Posts
    533

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    No DPF nonsense in my 2009 45hp cdi
    I broke a 45 and have saved the exhaust so that I can use it when my DPF starts giving problems.

  9. #19

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    No DPF my old Peugeot 207 1.4 HDi 70 diseasel from 2009. The Ford Fiesta and Fusion with the same spec engine didnt either.

    DPFs themselves werent made mandatory on new cars with Euro V, but the side effect of the regulation made them almost unjversal as only the smallest, lowest stressed diesels could pass Euro V without one.
    2004 Smart Fortwo Passion Cabro, low miles, commuting scoot.
    2016 Kia Sportage 1.7 diseasel, family wagon.
    1991 Yamaha FZR600 3HE7 Kocinski edition, owned since new.
    8 x bicycles. What can I say, I like bikes!

  10. #20
    Join Date
    Jun 2005
    Location
    Aberdeenshire
    Posts
    2,010

    Default Re: 451 Smart Cdi 54 HP - A real Boneshaker

    Quote Originally Posted by Chopper View Post
    No DPF my old Peugeot 207 1.4 HDi 70 diseasel from 2009. The Ford Fiesta and Fusion with the same spec engine didnt either.

    DPFs themselves werent made mandatory on new cars with Euro V, but the side effect of the regulation made them almost unjversal as only the smallest, lowest stressed diesels could pass Euro V without one.
    Some car manufacturers were less than honest.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

     

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts