Light blue smoke from the exhaust

Tiny
ABRAHAM HAACK
  • MEMBER
  • 1997 PLYMOUTH NEON
  • 2.0L
  • 4 CYL
  • AUTOMATIC
  • 155,730 MILES
Not sure when I press the gas pedal a little light blue smoke comes out but wasn’t doing that when my buddy test drove the car before I bought it. So I am not good at problems with cars.
Tuesday, September 10th, 2019 AT 2:41 PM

17 Replies

Tiny
KASEKENNY
  • MECHANIC
  • 18,907 POSTS
Hi,

Blue smoke is oil burning in the combustion chamber and coming out the exhaust.

I would suggest checking the oil level each time you fill up with gas just to make sure you are not getting low. Then keep a case of oil in the trunk so that you can top it off as needed.

This is caused by the rings not keeping the oil out of the combustion chamber and will only get worse. If the engine was overfilled with oil then that will cause the same thing because the crankshaft will splash the oil up onto the cylinder walls and gets burned out that way. Once it is put back to the proper level this will stop.

Here is a guide that explains the condition in a little more detail:

https://www.2carpros.com/articles/blue-smoke-from-engines-exhaust

Let me know if you have questions.
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Tuesday, September 10th, 2019 AT 2:58 PM
Tiny
ASEMASTER6371
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Good evening,

Blue smoke indicates burning oil.

I would have a wet and dry compression test done. If there is a difference of more than 15% on each cylinder, the rings are worn and that is the reason for the smoke.

https://www.2carpros.com/articles/how-to-test-engine-compression

Roy
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Tuesday, September 10th, 2019 AT 3:09 PM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
Can you still drive it like that?
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Tuesday, September 10th, 2019 AT 3:49 PM
Tiny
ASEMASTER6371
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Yes, you can but keep an eye on the oil level.

Roy
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Tuesday, September 10th, 2019 AT 3:52 PM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
Okay, thanks for your time.
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Tuesday, September 10th, 2019 AT 4:27 PM
Tiny
ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
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Tuesday, September 10th, 2019 AT 4:53 PM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
Would the light blue smoke go away if it’s been sitting probably not the issue though just wondering.
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Wednesday, September 11th, 2019 AT 5:11 AM
Tiny
ASEMASTER6371
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No, not really.

There is oil in the cylinders and that's why it is burning blue.

Roy
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Wednesday, September 11th, 2019 AT 5:17 AM
Tiny
KASEKENNY
  • MECHANIC
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I agree. The issue is the bottom ring on one or multiple of the pistons is allowing oil into the combustion chamber. So when he says that it’s burning oil that’s how it’s getting in there. If the car has been sitting more than likely these rings are seized and allowing oil past them. There is a small chance that as the car is run they could release and start blocking the oil again but this is a very small chance.

Roy†s advice of just checking the oil level regularly is your best course of action at this point and get as much life out of the engine as possible.
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+1
Wednesday, September 11th, 2019 AT 5:29 AM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
Then that’s what I will do.
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Wednesday, September 11th, 2019 AT 5:32 AM
Tiny
ASEMASTER6371
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Keep us updated.

Roy
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Wednesday, September 11th, 2019 AT 5:34 AM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
I will keep you updated and how much to fix probably not worth fixing.
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Wednesday, September 11th, 2019 AT 5:53 AM
Tiny
ASEMASTER6371
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You would be talking about an engine overhaul.

That would be around $3,000.00 to $4,000.00.

Roy
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Wednesday, September 11th, 2019 AT 5:55 AM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
I am running it until it dies then I will keep filling the oil.
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Wednesday, September 11th, 2019 AT 6:05 AM
Tiny
ASEMASTER6371
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Sounds like a plan.

Roy
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Wednesday, September 11th, 2019 AT 6:08 AM
Tiny
ABRAHAM HAACK
  • MEMBER
  • 8 POSTS
How many miles can you go if your burning oil but filling it?
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Wednesday, September 11th, 2019 AT 6:19 AM
Tiny
ASEMASTER6371
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You can go a lot of miles. Just do not let it get low in oil.

Roy
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Wednesday, September 11th, 2019 AT 6:23 AM

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