Andrew

You cannot just replace the EGR on the system.

After the EGR valve is replaced or after the PCM is replaced/reprogrammed, the EGR valve must be initialized by the PCM via IDS. The servo motor acts as a DC motor that sets the requested opening cross-section of the EGR valve.

Also it will be a safe bet, The PCM will require a Update for EGR valve software weakness.

Actuation is by means of the PCM using pulse width modulation. The exact position of the EGR valve is established via the position sensor.
It is therefore a closed control loop.

Note: Each time the engine is stopped, a cleaning
mode is activated by the PCM, whereby the EGR
valve is moved from its fully open position to a
completely closed position
(by means of maximum activation of the DC motor).

However, the longer the engine is in operation, the greater the likelihood of residues forming on the valve seat of the EGR valve as a result of the exhaust gases flowing past it. These residues can cause the mechanical closing point of the EGR valve to shift. For this reason, the closing is re-adapted at regular intervals. Consequently, the position sensor also retains its precise measurement after a long period.

So basically the EGR DTC faults will return again once a few drive cycles are completed.



On a variable turbocharger, the boost pressure is regulated by adjusting the guide vanes. This means that optimum boost pressure can be set for any operating condition. The boost pressure actual value is measured via the MAP sensor. The set value depends on the When a control deviation occurs, the guide vanes of the variable-geometry turbocharger are adjusted via the boost pressure control solenoid valve.


Hope this helps a little , its not as simple has most people think it is.

Professional Diagnosis and Fixing modern cars requires lots of very expensive equipment , many hours of technical training , access / subscriptions to manufactures data and years of experience.

Garage general does not mean you can fix / diagnose every job that comes through your door.

Take the Automatic gearbox for example if a car turned up with a gearbox fault , 99.9% of garages ship it out to a auto gearbox specialist.

trying to Diagnose faults on modern vehicle systems is no different. Most jobs require a specialist to carryout a full evaluation of what's wrong with the car.

Just by reading your post , its sounds like you are just guessing at what is wrong with this car.

did you test & confirm 100% the EGR valve was faulty. Or was it honestly, lets fit this £200 part pray it fixes it.????

As regards to the MAP sensor , I would be 95% sure that there was nothing wrong with the original sensor. But if you knew how it worked and understood how to it test , then you would no for sure your self.

please do not take this the wrong way and get all upset.

Its just advise, seek out a local specialist that's close to you and form a good working relationship or become the specialist...

I have been saying it on this forum from the very start " if you do not understand how it works how can you fix it"