Stalling or Insufficient EGR error

[PierreNel1982]

Hi All.

I recently had a situation one day when driving the car would barely pull and then refused to idle and die. A half educated guess that it was getting too much EGR flow and I pulled the vacuum pipe off the input onto the EGR valve (just to get me home). Presto and the car ran perfectly. I got the Insufficient EGR error (P0401) very quickly. After a few days I reconnected the pipe, cleared the error and the car ran fine but the error came back(P0401). Making me think the EGR valve or Solenoid had failed, which was causing the odd behavior to start with. I replaced both of those this weekend and fired up and it started idling rough and dying on the spot. Pulling my hair put I disconnected the MAP sensor and the car runs fine, with reduced power in the higher revs. I reconnected the MAP sensor and got the (P0401) error again but with normal power delivery, then half an hour later while driving it started sputtering then died.

This makes me thing I replaced the wrong bits to start with and it was the MAP all along. I have ordered a replacement.

Any other sensors that I should consider replacing? I replaced the MAF sensor 18 months ago, so dont think its that.
Oxygen sensor in exhaust? I have a simple code reader, should I get a better one to help diagnose errors better?

My mechanic currently is useless he said my EGR valve was gone and a massive quote to replace.

[marti]

You really need a BMW specific code reader with these beasts or you'll end up buying lots of parts for no reason.

[PierreNel1982]

Any code reader you recommend?

[PierreNel1982]

I should have added that I initially took the car for diagnostics and the code retrieved was
4501 : Digital Diesel Electronics(DDE) Exhaust Gas Re circulation (EGR) Control Deviation
4262 : Digital Diesel Electronics(DDE) Cylinder 6 glow plug activation.

I was quoted the better part of £700 to replace the EGR valve and glow plugs(Insane Price in my view). I did this all myself this last weekend and changed the EGR solenoid also.

After replacing the above
Im still getting the 4501 error on 2nd startup but car runs perfect with full power when cold. Later on 10 mins after warming up, the car splutters goes into a strange limp home mode or dies altogether. It barely moves under its own power. With no errors at all.

[marti]

Does the EGR fitted on your model have an electrical connector or is it vaccum controlled???...if electrical I think you may find it needs coding to the car?

[PierreNel1982]

vacuum operated via a solenoid. This solenoid I have also replaced along with the EGR valve and glow plugs mentioned above.
If its of any help, I do still have the swirl flaps installed also operated via vacuum.

In my view after all the work I have had done.
I have replaced EGR valve and EGR vacuum solenoid, vacuum lines are fine with no leaks , tears or frays.
All I can think it might be is MAP sensor or oxygen sensor in DFP or the swirl flaps are doing something which they should not be.
Considering the only error that comes up is 4501, despite me having changed all associated parts. Make me now think it might be oxygen sensor. Getting to that isnt easy.

[marti]

Just a question did you replace the EGR with a Pierburg or a cheapo one???....you could also un plug the MAF it will run on default settings.....a bad cam sensor will also show the symptoms your getting...once warmed up you get the problem your having.

[PierreNel1982]

Its not a Pieburg but not a cheapo. went for middle range in price.
Car is behaving same as it was before changing EGR valve and solenoid, telling me those weren't the culprits.
EGR error on 2nd startup and then later on after warmed up the rough idle/stall and no power at all syndrome.

Changed MAP last night, same error 4501 came up. Even when the MAP was unplugged I was getting 4501 error and
MAP low circuit warning. Meaning it probably isnt the MAP causing the 4501 error.

Reset this morning and unplugged the MAF. Two errors for Low voltage and incorrect Mass Air flow reading, but no EGR error after 2 starts. I think this might be it. I will reset errors and unplug camshaft sensor to see how the errors come up.

[PierreNel1982]

Update:
No real luck so far. After resetting and then unplugging MAF, resetting and then unplugging MAP,resetting and then unplugging Camshaft position sensor I still got P4501 with the relevent unplugged sensor error each time. So I dont think its any of those sensors

So I have located, downloaded Rheingold and BMW Standard tools onto my old Laptop and ordered a D-can cable.
I hoping I can get the code error in detail to understand what sensor/instruction is driving it to occur and working out whats going on.

There is also coding software, I could possibly code the EGR 4501 error out and leave it physically disconnected. That is very unlikely as that playing around and running the risk of bricking the car.

Anyone have experience of using Rheingold and BMW tools only for investigative diagnostics, not any recoding/mapping.

Cheers

[marti]

It could well be your Lambda sensor.....unplug that and see what you get...

[PierreNel1982]

Out of all the sensors I was thinking, knowing my luck its that one