Hi everyone !
My 2007 Continental GT is idling rough most of the times , CEL is coming on , codes are coming back :

P0548 - Exhaust Gas Temperature Sensor Bank 2
P2563 - Turbocharger boost control position sensor
Any advice ?

 

Watch the fuel you put in those selds…

only 93 and above
Shell, BP or Sunoco

nothing else. Here in Florida any other brand makes rough idle.
Might not be it but it was for me.

 

The rough idle and turbo boost control position sensor faults are probably resultant of a vacuum leak. To get an idea of what is involved an Internet search "vacuum test Bentley Continental". Essentially the vacuum lines need to be assessed before progressing to the next step.

The exhaust temperature sensor will not fix the above problem. However consider replacing the exhaust temperature sensor. They commonly fail. The sensor protects the engine during turbo boost.

 

Thanks , I'll definitely check the vacuum test.
One more symptom I forgot to address , when I step on the brake after engine start , the brake pump is working for about 1 - 2 min and then stops until I press the brake again.
Is this also might be related to vacuum leak ?

 

Yes, The vacuum leak is often revealed with excessive vacuum pump run time when pressing the brakes.

 

I'll post the update once I figure it out.
Thanks for your help !

 

Where is this sensor located ?
Also , where is turbo boost position sensor located ?
Another question , would a faulty MAF sensor cause a similar symptoms and codes ?

 

The exhaust temperature sensor, bank (2) Is buried behind and below the airbox driver side US. There's a probe going into the exhaust at the back of the engine.


I believe the Turbo boost position sensors are located above each intercooler.. The boost position sensor is more like a map sensor. A vacuum leak will cause this sensor to read ironiouslyly.

A bad MAFs can negatively influence performance. However a vacuum leak can negatively influence MAF sensors, there are two.

Without performing a proper smoke test to evaluate the vacuum lines could result in unnecessarily replacement of parts.

BTW: Most Here use Ross Tech VCDS. This system gives a rather thorough and deep analysis of the different modules on the Bentley.

 

If this is a vac leak, luckily you have a 2007 which means you can replace vac lines with steering rack out only, or run your own bypass like I did to get away from the back of the engine.

I believe you can also replace the PCB of the EGT sensor as well, rather than the entire sensor.

 

I don't think that's necessarily true. The vacuum line switch was a mid-year 2007 change.

 

Update:
I found a cracked dip stick , sealed it and rough idling is gone , however when I start driving CEL is flashing , codes are:
P0300 - multiple cylinder misfire
P1914 - pressure sensor for brake booster
Every time I press the brake , the pump is still working for about 20 sec.
If I step on the brake , the pump doesn't stop .

I inspected the vacuum lines behind and near the intake, they look good.
I can hear the air in the master cylinder area , but I'm not sure , the only vacuum hose I found there looks good..
I guess my next step will be removing the wheel well and checking the pump and vacuum lines.
Any guidance for that ?​​​​

 

Good catch on the dipstick.

A visual inspection of (some) of the vacuum lines is fine.

Usually vacuume line cracks are behind the engine along the firewall above the steering rack. The pressed metal barbs in the plastic lines is where the usual cracks are. This condition is not visible with engine in. A smoke test is the proper technique.

Anyway, The vacuum pump is located inside the driver's side wiheel well. Remove the wheel well plastic liner. The blue tank is the vacuum reservoir. Check that the top rubber vacuum line seal is securely in place.

As the vacuum leak source changes the sensors affected change which trouble codes pop up. This is why changing sensors is sometimes not the best action.

Careful with the misfires hard on catalytic converters.

 

Silvertone - did you do that bypass work yourself or did a shop do it for you? Sounds like a good option if/when my car needs the same.

 

So I removed the wheel well and borrowed a smoke machine.
I watched the video and the guy plugged the intake inputs into the turbos. Is this necessary or can I just seal the inputs ?

 

Great on getting a smoker!

Disconnect the line above the blue vacuum pump reservoir. Connect the smoke tester to that discnected 8mm line that passes into the engine bay. Perform the smoke test and see what happens☆. Next if no leaks are found continue testing as per the YouTube video to make sure.

☆A significant cracked vacuum line will smoke out without plugging the intake....