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PatMey

Black smoke and high fuel consumption in the Seat Leon 2012: Possible causes and solutions

Unsteady engine

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Check engine light on

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Poor fuel economy

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Loss of engine power

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Jerking on acceleration

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Black smoke from exhaust on acceleration

Hi guys, I have problems with my Seat Leon, year of manufacture 2012, gasoline engine and 98765 kilometers on the speedometer. Currently I notice suspicious black smoke when accelerating, the check engine light is on, the engine loses power and is restless, it jerks when accelerating and the fuel consumption is too high. I'm afraid it's the lambda sensor heater. Have any of you had similar experiences with these symptoms? I would like to hear your experiences and tips before my next visit to the mechanic, as I had quite a disaster last time. Many thanks in advance!

(Translated from German)

4 comment(s)


AliWerner

Hey, I had similar problems with my Seat Ibiza, built in 2009. As soon as I saw the first signs, I suspected that it could be the engine control unit. After a visit to the garage, it was confirmed that the engine control unit was faulty. The symptoms were almost identical to yours: black smoke, the engine control light lit up, rough engine running, increased fuel consumption and strange jerking when accelerating. The whole situation was quite serious and really worried me. They then repaired the engine control unit at the garage and once the car was back, it ran like clockwork again. So I would recommend that you visit a garage as soon as possible so that it doesn't get any worse. Hope that helps you! And don't worry, it's quite a common problem with our models.

(Translated from German)

PatMey (Author)

Hey, thanks for the tip and the reassurance! That sounds really similar to what I'm going through with my Leon right now. So it turned out to be the engine control unit in your case, hmm... Can you remember what you paid for the repair and if any other problems came up afterwards? I really don't want to miss anything before I go to the garage. Thanks in advance!

(Translated from German)

AliWerner

Hey, sure, no problem. So yes, in my case it actually turned out that the engine control unit was faulty. The repair cost me €1000, which certainly isn't cheap, but since then everything has been working as normal again. The good thing is that the issue with the lambda sensor heating, which you feared, was also resolved for me after the workshop visit. I had no further problems after that. Make sure you get it checked out at the garage, it will definitely pay off. Hopefully that will give you some peace of mind. All the best with your Leon!

(Translated from German)

PatMey (Author)

Hey, that really helps me a lot, thank you very much! Phew, 1000€ is a bit of a pain, but if it really solves my problem, then that's fine. And the news about the lambda probe heater is good news too. Well then, let's see what the mechanic says. I'll take your advice on board and mentally prepare myself for the large amount. Hopefully everything will go as smoothly as it did for you. Thanks again for the helpful tips and reassurance. Have a wonderful day and stay healthy! Thank you very much and see you next time!

(Translated from German)

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