Bedelon Posted July 1 Share Posted July 1 My 2008 BMW E91 320D with an N47D20A engine is experiencing EGR problems. The issues began two years ago when the vehicle suddenly stopped and lost power. This was determined to be caused by a faulty EGR valve, which was subsequently replaced by a workshop. Subsequently, the vehicle operated well until it underwent maintenance at the same facility this autumn to replace the valve cover gasket. Subsequently, the automobile has had recurring problems with the egr valve, resulting in unpredictable power loss and stalling. This may often be attributed to the egr valve being stuck in the open position. Nevertheless, I have dismantled the EGR valve, thoroughly cleaned it, and verified that it is able to move without any obstruction. However, the issue persists. I Upon consulting Realoem, it was seen that the automobile is expected to have a single vacuum control unit and a single pressure converter, both of which are linked to the egr system via the vacuum hoses. However, I own just the pressure converter, and it seems that the connection for the vacuum control unit is merely attached to a black plastic component that serves the purpose of concealing the connector. I purchased the vacuum control unit and a set of vacuum hoses to ensure proper connectivity. However, when examining the genuine original equipment manufacturer (OEM) specifications, it is evident that there should be a vacuum box present, which is directly linked to the exhaust gas recirculation (EGR) cooler. When I inspect my EGR cooler. There is an absence of anything at that location, and it seems inappropriate for anything to be present there. The vacuum box is linked to the vacuum control unit, along with a t-hose that links the egr valve, pressure converter, and intake. If my comprehension is accurate. Is there anybody who has a euro standard N47D20A engine and can provide a photograph of their EGR Cooler and valve without the vacuum box attached to the cooler? Alternatively, could you provide instructions on how all the components should be interconnected? Currently, I am unable to financially support an egr deletion for my vehicle. Therefore, my primary objective is to restore my car's performance to its optimal state. Thank you in advance! Link to comment Share on other sites More sharing options...
Sumoto Posted July 1 Share Posted July 1 Could you please provide a photograph of your item so that I may better understand its appearance, since I am having difficulty visualising it based on your description. The previous version of my vehicle, the n47d20a, was equipped with an electronic exhaust gas recirculation (EGR) system, but also featured a vacuum-controlled cooler bypass. In some older models, a vacuum EGR valve was also included. Link to comment Share on other sites More sharing options...
Bedelon Posted July 1 Author Share Posted July 1 Certainly! There is a single vacuum line that connects the intake manifold to the pressure converter. Additionally, there is another hose that connects the EGR valve directly to the pressure converter. An electrical connection is unattached and housed inside a black plastic component. This is the condition in which I purchased the vehicle in 2019, and as previously said, it has functioned well in this state. However, I believe there is a deficiency since the electrical connection is only resting in a black plastic component. Shouldn't it be linked to a hoover control unit or some other device? Link to comment Share on other sites More sharing options...
Bedelon Posted July 1 Author Share Posted July 1 Link to comment Share on other sites More sharing options...
Jollyno Posted July 1 Share Posted July 1 I do not recall any vacuum-related components on my EGR or cooler. I will examine the matter at a later time and return somewhat earlier, namely at 5:37am. Link to comment Share on other sites More sharing options...
Sumoto Posted July 1 Share Posted July 1 Is the plug at the front the one you are referring to? If such is the case, it is often due to the use of a pressure converter for the cooler bypass. I can identify the difficulty you are experiencing. The split breather pipe is causing issues with the engine's operation and is affecting the plausibility of the EGR and MAS air flow. I would suggest replacing the breather pipe, clearing any error codes, and then assessing the situation to determine its effectiveness. Link to comment Share on other sites More sharing options...
Bedelon Posted July 1 Author Share Posted July 1 Indeed, the breather pipe requires attention since it seems much larger after the tape is applied. However, because it is the tiniest break, I am uncertain about its potential impact on the EGR system. Could you kindly elucidate the impact of the breather pipe on the EGR system? Indeed, the pressure converter is linked to the EGR valve, which is responsible for regulating the opening and closing of the valve. The issue arises when the automobile experiences stalling and exhibits poor performance. Most likely, the valve is experiencing a problem where it remains in an open position. Nevertheless, the valve has been thoroughly cleaned and is now capable of unrestricted movement. I don't comprehend why it would get stuck in an open position and result in these problems. Link to comment Share on other sites More sharing options...
Bedelon Posted July 1 Author Share Posted July 1 I have used bimmercode to scan codes and have obtained the following codes pertaining to motor electronics: The code 40D4 refers to the regulation of exhaust gas recirculation (EGR) with a specific focus on position control. The 4C9E code indicates a plausibility issue with the exhaust gas recirculation valve. The number 4501 is equal to 4501. Control of exhaust gas recirculation and variation in control When I detach the vacuum pipe connecting the intake manifold to the pressure converter, the vehicle operates smoothly without stalling. However, the sole drawback is that it lacks responsiveness when the throttle is applied. Therefore, it is suboptimal. Could the pressure converter be the defective component? After replacing the EGR valve with a new one from BMW Two years ago Link to comment Share on other sites More sharing options...
Sumoto Posted July 1 Share Posted July 1 I am referring to the socket located at the front of the cooler, not the converter on top of it. The breather pipe allows unmeasured air to enter, disrupting the air and exhaust gas recirculation (EGR) balance. The DDE system relies on a certain quantity of air based on the mass airflow (MAF) measurement and a specific amount of EGR based on the opening amount. However, if the system pulls in unmeasured air, it leads to operational problems and triggers plausibility codes. It is possible that you have a valve or converter issue, however it is not possible to precisely evaluate due to the divided pipe. Link to comment Share on other sites More sharing options...
Bedelon Posted July 1 Author Share Posted July 1 Understood. Thank you for the information! Yes, if I understand well, the plug should be connected to a hoover control unit. Are there hoses linked to a vacuum box that is positioned on the EGR cooler? However, based on my observations, I do not own the vacuum box or a suitable location on the cooler to accommodate it. Therefore, I would appreciate a photograph of an N47D20A engine or assistance from someone knowledgeable about whether my EGR is properly linked with the corresponding hoses. I will replace the breather pipe this week to see whether it provides any improvement. Link to comment Share on other sites More sharing options...
Insignia GS Line Forum
Insignia GS Line Forum
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now