Black Soot from Exhaust and Rough Idling - Need Help!

Issues with Black Soot and Rough Idling

I’ve been experiencing some troubling symptoms with my Chevrolet lately, and I’m hoping someone here can help me figure out what’s going on.

The Problem

I’ve noticed a significant amount of black soot coming out of the exhaust, which isn’t something I’ve seen before. Along with this, the engine has been idling rough—it feels like there are misfires happening, and sometimes it even shakes a bit.

Possible Causes

From what I’ve read, the presence of black soot suggests there might be a rich fuel mixture problem. Here are a few things that come to mind:

  • Faulty Fuel Injectors: Could they be leaking or not functioning properly?
  • Bad Sensors: Is it possible that a sensor failure could lead to an incorrect air-fuel mixture?
  • Spark Plugs/Ignition System: Could these be causing the rough idle and misfires I’m feeling?

What I’ve Done So Far

I’ve checked the air filter, and it seems clean. I haven’t looked into the injectors or spark plugs yet, but I plan to.

Seeking Advice

  • Has anyone else faced similar issues? What was the solution?
  • What would you recommend checking first? I want to tackle this problem efficiently without unnecessary expenses.

I appreciate any insights you guys can provide! Thanks in advance for your help!

1 Like

I’m sorry to hear about your rough idling! Black soot usually indicates incomplete combustion. Check your spark plugs and fuel injectors; they may need cleaning or replacement.

3 Likes

That’s interesting! Could it also be related to low-quality fuel? I’ve had that issue before.

Absolutely, beckrachel! Bad fuel can cause poor combustion, leading to soot. Plus, check if there’s oil leaking into the combustion chamber, which can also create black smoke.

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Well, if the engine is running rough along with the soot, it might indicate a deeper problem like worn piston rings or valve issues. Might be time for a compression test?

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I had similar issues last year! Turned out to be a clogged air filter. It’s amazing how something so simple can really impact performance!

Totally! I wouldn’t have thought something like that would cause soot issues. Definitely going to check that out.

Also, don’t forget to check your engine’s timing! If it’s off, it could also be a culprit in both soot and rough idling. Have you had it checked recently?

Yes! A friend’s car was a soot monster until they adjusted the timing. The poor thing was just out of sync!

Haha, I feel like my car’s doing the tango sometimes! But really, thanks for the tips, everyone.

It could also be as simple as low oil. If the oil level is low, it can lead to a host of problems, including soot. Check it out!

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Really good point! I often forget to check that regularly. I’ll make it a habit! Thanks!

Absolutely! I found that a clogged air filter can cause rough idling and increased soot. It’s a simple fix - just check it and change it if it’s dirty!

I had a rough idling issue once, and it turned out to be the spark plugs. They were all gunky with soot. Replaced them and my engine ran smoothly afterward!

That’s a good point, eddie92! Spark plugs can really affect engine performance. Did you notice any specific symptoms before you replaced them?

Yes, my car would shake a lot while idling, plus the exhaust was black. After changing the plugs, it was like night and day! I definitely recommend checking them if you see soot.

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I’ve had soot issues recently as well. Are there specific diagnostic tools you all recommend for checking the engine performance?

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For diagnostics, a good OBD-II scanner can do wonders! It helped me pinpoint a fuel injector problem that was causing my rough idle. Worth investing if you’re experiencing persistent issues.

Mary49, that’s insightful! I’ve never used an OBD-II scanner before. Is it user-friendly for someone who’s not very tech-savvy?

Definitely user-friendly! Just plug it in and follow the instructions on the app. It’ll save you so much time troubleshooting.