Oil Change - Car not happy when hot

[rb0135]

Originally Posted by powers1

Rob,
We get here quite a few X5s and X3s 3.0D with same symptons as yours,even under warranty!Only difference is ,they come in with EML on and after we perform diagnostics,90% of the time its the EGR solenoid that brings up the error.First test we do(yes..you guessed it),is disconnect the vac pipe.Then we replace solenoid..problem solved!
Cleaning the EGR valve wont do any harm but thats not the problem,because you have proved that with vac pipe disconnected ,the car is fine.With the pipe disconnected ,the egr is closed (no exhaust gases to inlet !) and although it may not be sealing 100%,its seems to be shut enough for it not have an influence in the cars performance.
What opens/closes the EGR valve is the ECU from instruction from EGR solenoid,so this would be be your first suspect

Thanks Powers1 again..

Ok, i hear ya.. leave the MAF alone... Good, it looks like as job and a half to do anything with it anyway.

I will work on the EGR. I will clean it (just to remove the junk which I am sure it will have). I have tried to trace the vacuum tube back to the control unit (according to the realoem diagram, there is a small control unit, which I presume you are referring to is the solenoid (part #1 in RealOEM.com * BMW E53 X5 3.0d Vacuum control-AGR)

Is this correct? or do you mean in the EGR unit itself?

I think i would rather fix it than have the pipe disconnected.

However, I will leave it disconnected for the short term (might be a week or two before I get a chance to clean and get the part needed), so that will be a good test.

Thanks for everyones help. I am so relieved I actually know the area of the fault.

Rob