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KaiserIlseFan

2012 Volvo S40 Gasoline Engine Issues: Black Smoke, Engine Light, Rough Start, and Loss of Power

Stalling while idling

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Jerking on acceleration

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Car won't start

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Loss of engine power

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Black smoke from exhaust on acceleration

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Shaking while idling

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Check engine light on

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Unsteady engine

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Longer cold start time

Hey folks, I've got a 2012 Volvo S40, Gasoline engine, acting up. It's showing black smoke when I accelerate, and has a persistent check engine light. Recently, it's not starting as smoothly when cold, and I've noticed a loss of engine power overall. The engine isn't steady, judders on acceleration, doesn't start some times, and tends to stall or shake while idling. I'm suspecting an injector issue but would love some input. Has anyone encountered this before? What did your workshop do to sort it out, and how was your experience? Any tips or pointers would be much appreciated!

(Translated from German)

4 comment(s)


NickyKai

Hey there. I had a similar challenge with my 2014 Volvo S60. My level of car expertise leans towards some experience, so I also reached out on a forum like this for help. Ended up at my local workshop, my able mechanic did some tests and concluded that the injector was internally defective. This was causing all the problems I was having including the black smoke and engine judder. Had to replace it to get the car back in shape. It cost me a hefty 515 Euro, but it was worth it. The car's running pretty smooth now. By the way, did you check the mileage on your car lately? And is the idling problem occurring when the car is both hot and cold? Getting this info could help in understanding the depth of the problem. Also, consider digging into your engine diagnostic to see if it flags up your injector. That might confirm your suspicions. Good luck!

(Translated from German)

KaiserIlseFan (Author)

Hey, thanks for the response! Checked the mileage again and I'm at 40208 KM, this issue started occurring after my latest service actually. In response to your question, the idling problem occurs mostly when the engine is cold but sometimes I notice it when it's hot too. I think it’s time I should also consult a mechanic to conduct a thorough inspection. Your experience gives me an idea of what to anticipate. Didn’t know I could check my engine diagnostic, I’ll definitely have to take a look at it. Thanks for the tip, I really appreciate it!

(Translated from German)

NickyKai

No worries,! Glad I could help. Sounds like a good plan to get your car checked out by a professional, because frequent shaking and black smoke are certainly not normal, especially for a vehicle with that low mileage. Keep a close eye on when the problem occurs - the more information you can provide to your mechanic, the easier it'll be for them to diagnose. The engine feeling unstable along with the stalling while idling and jerking at acceleration, it does lean heavily towards a fuel system issue - and the injector is a major part there. But, it's always best to get a reliable diagnosis before jumping into conclusions. Do remember to ask your mechanic to do thorough diagnostics, as they can bring out the key issues which you may not see or feel while driving. Hopefully, getting it fixed won't burn a hole in your pocket! Fingers crossed it's no biggie. Keep us posted on what happens, and drive safe!

(Translated from German)

KaiserIlseFan (Author)

Hey, cheers! That's some solid advice. I'll definitely make sure to note down all these erratic patterns my car's been showing and hand over every minute detail to my mechanic. That should help him understand the problem in a better way. A fuel system issue, huh? Sounds daunting. But I guess the way the car's been losing power and behaving recently, it does fit. A thorough diagnostic it is then. Can't ignore these warning signs and ain't looking forward to my pocket getting burnt either. Let's hope this doesn't turn into a budget buster. I'll definitely keep you all in the loop once I get things sorted - fingers crossed it isn't something too major. Again, thanks a ton for your help, and safe driving to you too!

(Translated from German)

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