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MZimmermann

Opel Signum 2005: Black smoke and engine indicator light signal possible exhaust problems

Check engine light on

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Strong exhaust smell

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Loss of engine power

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Black smoke from exhaust on acceleration

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Exhaust leak

Hi guys, I'm a bit worried about my Opel Signum, built in 2005, with a gasoline engine and 195,440 km on the odometer. My car shows various symptoms: it smokes black when accelerating, the check engine light is on, it runs out of power and there seems to be an exhaust leak. The exhaust also smells quite strong. I suspect that the whole thing has something to do with the exhaust aftertreatment, but I'm no expert. Now I'm worried that the mechanic didn't do the best job last time and before I go to him again, I wanted to hear your opinions and experiences. Have any of you had similar problems and could give me tips on what to do or where I should go? Thanks in advance!

(Translated from German)

4 comment(s)


HBauer

Hello, I have actually had similar problems with my 2002 Opel Vectra. It seems to be the problem with the lambda sensor, just as you suspected. In my case, it was the defect in one of the lambda sensors responsible for exhaust gas regulation. The symptom was the same: black smoke, check engine light on and a few power losses here and there. When I had it checked at the garage, they had to replace the defective lambda sensor. It was a bit of work and took a few days, but after that the car ran perfectly again. So it would be a good idea to go back to the garage and ask them to check the lambda sensors. In the worst case, they may have to be replaced, but then it should run smoothly again. Hope that helps! Best regards!

(Translated from German)

MZimmermann (Author)

Hey, thanks for the tip! That's exactly the kind of info I was looking for. Do you still remember what you paid for it? And have you had any similar problems since then? Thanks again and best regards!

(Translated from German)

HBauer

Hey, I'm glad I could help! Well, I had to pay around €375 to have the defect in one of the lambda sensors repaired. I haven't had any more problems since then. And yes, you read that right, since the visit to the mechanic, the exhaust aftertreatment malfunction has also stopped. Since then, my car has been running like clockwork again! I hope that eases your worries a little. Sure, it's quite a lot of money, but hey, sometimes you just have to bite the bullet, don't you? And then hopefully you'll have peace of mind again and can just enjoy the ride. Greetings!

(Translated from German)

MZimmermann (Author)

Hello, thank you very much for your detailed answer! You have definitely helped me. I think I'll just bite the bullet and go to the garage. Even if it costs a bit, the main thing is that the car runs smoothly again and I can drive with a clear conscience. Thanks again for the help and advice! Bye!

(Translated from German)

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