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Discussion Starter #1
Hey everyone! Hope you are having a great Saturday!

I have a 69 Mustang, 302 with a 2 barrel carb and I noticed recently that there was some smoke coming from the exhaust pretty prevalent. The smoke is bluish with a little white in it. There are plums of smoke when i first start the car and when i hit the gas hard. if it is sitting idle or i slowly accelerate its almost unnoticeable.

I have messed with the choke in hopes that the issue may be that the mixture isnt rich enough but i havent seen any difference. I am looking at adjusting the idle mixture screws next but I wanted to ask the community before i started down that road again to see if anyone had any other thoughts or troubleshooting steps to take.
 

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There are plums of smoke when i first start the car and when i hit the gas hard. if it is sitting idle or i slowly accelerate its almost unnoticeable.
If you drive the car for 15 minutes and THEN hit the gas hard, does it smoke?
 

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Discussion Starter #3
If you drive the car for 15 minutes and THEN hit the gas hard, does it smoke?
I believe it did but ill test it for certain. would the idle mixture adjustment screws possibly cause this as well?
 

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Blue on initial starup after resting is usually leaking valve seals or worn valve guides. The oil drips down into the combustion chamber after you shut the motor off and the blue is the initial burn off of the oil. Blue after running for a while when under load is usually piston blow-by and bad rings. A compression test would tell you if the rings were ok.
 

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Discussion Starter #5
Blue on initial starup after resting is usually leaking valve seals or worn valve guides. The oil drips down into the combustion chamber after you shut the motor off and the blue is the initial burn off of the oil. Blue after running for a while when under load is usually piston blow-by and bad rings. A compression test would tell you if the rings were ok.
How do i perform a compression test?
 

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You procure a compression tester, remove all spark plugs, attach tester to one spark plug hole. Hold throttle wide open and crank engine over at least 3 or 4 revolution. Watch gauge rise. Record highest reading. Repeat 7 more times. Post results here for analysis.
 

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Buy or rent a compression gauge. You pull all spark plugs and screw in the compression guage to one cylinder at a time. Then you crank the engine for about 5-10 seconds and read the gauge. IIRC around 150PSI and above is pretty good. Also check for different results in each cylinder as you may only have one or two bad.

I see Asm109 beat me to it....
 

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You remove the spark plug and replace it with a fitting attached to a gauge. Here's what it looks like. Easily found. I bet an auto parts store loans it.
763152
 
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