Raw Fuel Out Exhaust

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KP

KP

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Have raw fuel spitting out of my exhaust. Ideas/suggestions please.

Thank You,

KP
 
Your supposed to have your fuel line running to the carb, not to your catalytic converter lol...Sounds like you have a no-fire on a cylinder and its flooding just that one.
 
JRDART said:
Your supposed to have your fuel line running to the carb, not to your catalytic converter lol...Sounds like you have a no-fire on a cylinder and its flooding just that one.
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How would I verify this?
 
Well Im not 100% on how you would do that Ive heard about it havent experienced it though
 
That's a really bad valve, causing no fuel burn and then it goes into the exaust.
What puzzles me is that it's not apparently getting ignited by the running cylinders.

I have to ask this and it's kinda joking but, the car is running and you have raw fuel out the exhaust???
Or it runs out when the car is not running?
 
what do you think Trail?? Could be a faulty wire? possibly a hammered valve?
 
JRDART said:
what do you think Trail?? Could be a faulty wire? possibly a hammered valve?
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Could be a wire/spark issue, but why is it running so rich that there is raw fuel getting all the way to the end of the exhaust?

I wish I could hear this car running.

Way over fueling the car would make it run terrible (if at all)
Raw fuel in the exhaust should be ingnited by the exhaust from the other cylinders causing a backfire in the pipes. (If it was a bad valve or no spark issue)
The totally weird part is that NO missing cylinder would EVER put enough fuel into the exhaust that would make it come out the back unburned.
 
Raw Fuel?? im not a super mechanic or anything but can this even really happen...seems if this was really possible the car could/would not even run...I cant believe it would not get ignited at some point....
 
catch it in a cup as it comes out-light a match and see if it burns-most likely it is water vapor that is coming out and condensing.
 
TrailBeast said:
That's a really bad valve, causing no fuel burn and then it goes into the exaust.
What puzzles me is that it's not apparently getting ignited by the running cylinders.

I have to ask this and it's kinda joking but, the car is running and you have raw fuel out the exhaust???
Or it runs out when the car is not running?
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When it is running. :)
 
Engine does not miss at all, smokes a little at idle and lot when the gas is smashed to the floor, has the same compression in every cylinder.

If you are standing behind the exhaust tips when the engine is idling it spits what appears and smells like black raw fuel.

Will post leak down results later.

Any other suggestions/ideas...
 
Hold someone has the answer for both of us...
 
How much? Drops or streams? I have only seen this is a late 90's Dodge van when the regulator went bad and it pumped fuel straight through the motor, filled the converter and muffler, and dumped the rest out the tailpipe. I'm talking tons of fuel. However, it couldn't possibly run and was hydrolocked. I have seen floats stick on carbs and dump fuel down the motor which could conceivably run to the exhaust, but again, with that much fuel, it ain't gonna run. I suspect you have condensation.
 
Mopar to ya said:
How much? Drops or streams? I have only seen this is a late 90's Dodge van when the regulator went bad and it pumped fuel straight through the motor, filled the converter and muffler, and dumped the rest out the tailpipe. I'm talking tons of fuel. However, it couldn't possibly run and was hydrolocked. I have seen floats stick on carbs and dump fuel down the motor which could conceivably run to the exhaust, but again, with that much fuel, it ain't gonna run. I suspect you have condensation.
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Somewhere in between. Remember when it is floored it smokes real heavy.
 
KP said:
Somewhere in between. Remember when it is floored it smokes real heavy.
Click to expand...

Black or blue?
The black stuff is just exhaust residue getting washed out by the condensation.
If you have black smoke when you stomp on it, it's getting way to much fuel and that is why the black is there in the first place.
Smog systems can cause condensation also, since they inject fresh air into the exhaust system and it then causes condensation.

I really suspect the camaro has this issue because of the smog system.
 
Pull the spark plugs and see if any of them are wet.
If they are all wet then look at troubleshooting the carb.
If only one plug is wet then you look into that particular cylinder valve train.

If the plugs are dry and look healthy/normal then the black liquid coming out of the exhaust is probably condensation with a little bit of unburned fuel residue mixed in with the black soot from a rich burn upon initial startup.

I once had a compression ring fail on one cylinder. The plug would fire but the fuel would not burn properly and the plug would be wet with fuel. Of course the compression test indicated which cylinder to address. I replaced the rings and the problem went away.
 
sounds like you my have a head gasket lecking.if it just started.that would be my gess take the cap off and see if it is puting comp.in the rad.or rev it up with cap off and see if water pushes out wen you let of the gas....Artie
 
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