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MatthiasMayerFan

BMW 1 Series gasoline engine with 189041 km: Symptoms of severe exhaust leak, increased fuel consumption and possible problems with the NOx storage catalytic converter

Black smoke from exhaust on acceleration

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Exhaust leak

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Poor fuel economy

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Check engine light on

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Loss of engine power

Hey guys, I'm a bit worried about my 2007 BMW 1 series, gasoline, with already 189041 km on it. Didn't have such a good experience with the mechanic last time. Now I have the following symptoms: black smoke from the exhaust when accelerating, check engine lights up, car loses power, exhaust leak and fuel consumption is not so great anymore. I think the NOx storage catalytic converter may be getting on in years. Have any of you had similar experiences, perhaps a tip as to what exactly could be going on? What are your experiences at the mechanic with such problems? I would really appreciate your help!

(Translated from German)

6 comment(s)


Best Answer

OliWag

Hey, I had a similar case last year with my 2004 BMW 3 Series, diesel. Also had loss of power, check engine constantly lit up and fuel consumption increased. The black smoke indicates that your engine is burning too thick a mixture. In other words, too much fuel and too little air. The problem in my case was the turbocharger, which for some reason was no longer building up enough pressure. I would also check the mass air flow sensor and the injection pump. The exhaust leak could also lead to the symptoms mentioned. If the exhaust is leaking, then the engine is getting incorrect values and this is controlling the mixture incorrectly. I can't say anything about the NOx storage catalytic converter, as I didn't have anything like that in my 3 Series in particular. I would really have the fault memory read out on your car. Maybe it's not that bad. I had all that done and of course it was a bigger story. But it's important that you get it sorted. Hope you have a more reliable car soon than I had. Good luck with it!

(Translated from German)

MatthiasMayerFan (Author)

Hey, thanks for your quick reply and the tips! It seems like you really know your stuff. I'll definitely have the fault memory read out and have the turbocharger, mass air flow sensor and injection pump checked. I'm sorry to hear that you had such problems with your 3 Series. Can you remember how much the repair cost you? And has anything else come up since then? It would be super helpful for me to be able to prepare for this. Many thanks in advance!

(Translated from German)

OliWag

Hi, I'm glad I could help you. I spent €1550 on repairing the NOx storage catalytic converter. But now everything is running smoothly again, it did a good job. The replacement wasn't cheap, but since then the problems have disappeared. So I can only recommend having it checked. You're really right, it pays to go to a mechanic. Good luck with your car, hope the repair isn't too expensive!

(Translated from German)

MatthiasMayerFan (Author)

Cool, thanks again for the information! It really makes things easier if you have a point of reference. 1550€ is a lot of money, but if it's all fixed after that then it's probably worth it. Will definitely get the NOx storage catalytic converter checked and hopefully that will solve my problem. Have a good trip and hopefully we'll both be spared car problems in the future!

(Translated from German)

Michi

Hello, Error comes out NOx catalytic converter; Regeneration efficiency too low. New dpf installed since august last year. Error has been coming out since then, BMW 520, year 2015 230,000 km.

(Translated from German)

CarlyAdminNik

@Michi

Hello, Error comes out NOx catalytic converter; Regeneration efficiency too low. New dpf installed since august last year. Error has been coming out since then, BMW 520, year 2015 230,000 km.

Hello Michi, The error could be due to several factors such as faulty sensors (NOx or differential pressure), incorrect DPF installation, outdated software, exhaust leaks, inappropriate driving habits for DPF regeneration, or the use of low-quality fuel and oil. It is advisable to have a BMW specialist conduct a thorough diagnostic to identify the precise issue and update any necessary software or repair faulty components to resolve the error. Please keep us updated on your progress and let us know if you have any other questions.

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