When you look at the current technologies deployed by vehicle manufacturers like BMW and Mini to meet increasingly strict emissions targets set by the EU on diesel engines, it’s obvious that these technologies have been rushed to market and are not fit for the job.

Examples we’d like to point out are the diesel particulate filter (DPF) – a device that removes soot from the exhaust gas of a diesel engine, and the exhaust gas recirculation valve (EGR) – a device that recirculates exhaust gases through the engine cylinders. Both of these technologies are designed to reduce emissions, but they are not reliable and when they break they affect the performance of a vehicle considerably, or put it into limp mode – rendering one’s mode of transport completely and utterly useless.

And the kicker? It can cost thousands of pounds to have either of these components replaced, and there’s no guarantee that they won’t fail time and time again. In fact, some diesel car owners have found themselves in a vicious cycle with EGR valve failure, in the end giving up and replacing their pride and joy with a petrol car instead.

BMW and Mini EGR valve failure

Because EGR valves deal with dirty air, over time the valve can become clogged with carbon deposits that prevent it from operating properly.

While every vehicle fitted with an EGR valve is at risk, over the last 3 years we have seen a significant rise in the number of diesel BMW and Mini owners with EGR valve problems. All BMW engines from 2004-present (16d, 18d, 20d, 25d, 30d, 35d and 40d) are susceptible to EGR valve failure and the 1.6d and 2.0d engines are the same as in the Mini range, so there’s failure in these cars too. Symptoms of EGR failure include:

  • Lumpy idling;
  • Reduced throttle response;
  • Hesitancy to accelerate;
  • Stalling;
  • Knocking noises from the engine area;
  • Complete engine failure (won’t start).

And warning signs of failure include: Engine management light on dashboard.

If you are experiencing any of these signs or symptoms with your BMW or Mini, then it could be the EGR valve that is at fault. The good news is that there’s a cost-effective solution to complete EGR failure, and it doesn’t require the removal of the old part.

How we can help

We can diagnose issues with EGR valves by connecting diagnostic equipment to the car’s ECU, to read any fault codes. If there is a problem with the EGR valve, then the car’s ECU will tell our diagnostic equipment. OBD code P0401 is often the first one we find; this is a generic fault code that means there’s a problem with either the DPF or EGR. Further analysis will reveal the exact reason as to why your car isn’t running as it should.

If we find that the EGR valve is the cause of your BMW/Mini engine woes, then our solution is to delete the section of software on the ECU that tells the EGR valve to operate, and the section of software that allows the sensors on the EGR valve to communicate with the ECU – we then reprogram the ECU to compensate for the loss of this component.

So the EGR valve itself effectively becomes a dead part.

EGR software delete for BMW and Mini diesel engines

There’s 2 advantages to mapping out the software versus physically replacing the EGR valve:

1. Deleting the software is a lot cheaper, and;

2. Deleting the software is a permanent fix – remember that replacing the EGR valve with a new one does not guarantee it will not fail like its predecessor.

Furthermore, both the physical removal of the EGR valve and the deleting of EGR software is 100% MOT compliant – in fact, the EGR valve doesn’t even form a part of the current MOT test (19/10/2015). This may be tightened up in the future, but even if it is, it’s unlikely to be applied retrospectively (on older cars).

We have successfully performed this service on hundreds of BMWs and Minis and we can do the very same for you with a jargon-free service. So give us a call on 0800 458 1534 or from your mobile on 07590 196772 to find out more – or fill in our contact form and we’ll get back to you as soon as possible.

  • gordon mcleod

    hi there i have a fault code P0401on a BMW X5 E53 but i have a EGR bypass on and its vacum operated can you tell me what my problem be