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Engine spewing smoke out exhaust.

B

BessieBlue

New member
Joined
Mar 2, 2020
Location
Sonoma County
I replaced the oil separator and flame trap, but at this point, I don't know what else it could be. Any troubleshooting help would be much appreciated.
 
What color is the smoke?

White or light gray is usually coolant related, so likely the head gasket or in the worst case a cracked block or head.
Black is fuel, so the car would be running too rich. It will also probably smell like gas and your mileage will be crap.
Blue or blueish gray is engine oil. This would mean bad piston rings or oil leaking down through the valve guides. Although I could see this also being a head gasket if the part around an oil channel went.

When does it smoke? Acceleration, deceleration, cruising, or idle?

There are a lot of different conditions that can cause a car to smoke out the exhaust but you can tell based on the color of the smoke and what conditions result in smoke.

I don't think the PCV system would result in smoke unless you are getting really nasty blow by.

How does the oil look and is the consumption worse than normal? As 283SD mentioned, how is the coolant level over time? Is there any crap in the coolant?

What car? I assume it is the '84 245 you mention in your post history. So I am guessing a B23 motor.
 
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It's pretty blue-gray. I realized I didn't clean out the vacuum nipples when replacing the pcv, I'll try that and see if it clears up the problem.

spock345 said:
What color is the smoke?

White or light gray is usually coolant related, so likely the head gasket or in the worst case a cracked block or head.
Black is fuel, so the car would be running too rich. It will also probably smell like gas and your mileage will be crap.
Blue or blueish gray is engine oil. This would mean bad piston rings or oil leaking down through the valve guides. Although I could see this also being a head gasket if the part around an oil channel went.

When does it smoke? Acceleration, deceleration, cruising, or idle?

There are a lot of different conditions that can cause a car to smoke out the exhaust but you can tell based on the color of the smoke and what conditions result in smoke.

I don't think the PCV system would result in smoke unless you are getting really nasty blow by.

How does the oil look and is the consumption worse than normal? As 283SD mentioned, how is the coolant level over time? Is there any crap in the coolant?

What car? I assume it is the '84 245 you mention in your post history. So I am guessing a B23 motor.
Click to expand...
 
BessieBlue said:
It's pretty blue-gray. I realized I didn't clean out the vacuum nipples when replacing the pcv, I'll try that and see if it clears up the problem.
Click to expand...

Does the coolant level or oil level drop? What happens to the smoke when you accelerate and what happens when you decelerate? Does it just spew smoke at idle?
 
It was fine for about 60 feet and then started spewing from accel. Now it is doing it when I start the car as well. I'm leaking fluid at the front left corner of the car.


spock345 said:
Does the coolant level or oil level drop? What happens to the smoke when you accelerate and what happens when you decelerate? Does it just spew smoke at idle?
Click to expand...
 
That is the charcoal canister for the vapor emissions. It's supposed to have two hoses going to it from the throttle body. I presume that is what you are calling the air control valve. The canister gathers the vapors from the gas tank and a valve on the top opens when the engine is running to burn the fumes.
 
What are the characteristics of the mystery fluid (color, smell) leaking from the car? Any smell from the exhaust? I've found burning engine oil (indicated by blue/gray smoke) to have a distinctive smell. You can also check the spark plugs. Include a link to a picture of the plug tips and we can help you figure out what is going on.

dl242gt is right. A compression test is in order.
 
dl242gt said:
A bad head gasket. Or, a worn cylinder sucking in oil to burn.
Click to expand...

I was always taught that blue/gray smoke on acceleration meant valve guides/seals.

Although it sounds like OP's problem got worse since it happens at idle now. Might be a head gasket.
 
Smoke on acceleration is usually more mixture related. It's the smoke on decel when the engine has high vacuum that oil get sucked past worn guides and seals. Although with a clogged pcv system you can get oil smoke at any time but especially on decel.
 
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