Gas leaking out exhaust manifold?
txcougar
01-31-2004, 02:22 AM
I hope you guys can help us out. My brother in law has an 83 Buick Lesabre with a 307. He claims iIt appears that gasoline is somehow leaking out the exhaust manifold and it has been terrible on gas mileage since he bought it a couple of weeks ago. He's also smelled gas coming from the engine compartment at times. It seems to be running okay other than this leaking gas and it only seems to leak when he first starts the engine? Hope someone can help.
tomminajar
02-14-2004, 01:12 PM
I hope you guys can help us out. My brother in law has an 83 Buick Lesabre with a 307. He claims iIt appears that gasoline is somehow leaking out the exhaust manifold and it has been terrible on gas mileage since he bought it a couple of weeks ago. He's also smelled gas coming from the engine compartment at times. It seems to be running okay other than this leaking gas and it only seems to leak when he first starts the engine? Hope someone can help.
If Gas was leaking out Exaust manifold I doubt your brother in law would be around to tell you about it-
I am guessing you have an Electronic Q-jet . 3 guesses off top of my head - ALL FROM Experience - Is there black smoke out off the tail pipe (soot) ? Check the check valve on the Charcoal Canister you might be sucking gas right out of carb- /Ground the ALDL -turn ignition on- You should hear a rapid Clicking from the top of carb-if not the mixture controll solinoid is stuck- /
Is it hard to start first thing in morning ? Allmost all Q-jets leak after a few decades from the plugs in the bottom of the float bowl flooding the intake w/gas and emptying the float bowl- And don't forget to see if the float is stuck - If you find someone old enough to know what he's doing he can fix the q-jet (rebuild it in a hour) Don't go buy one fro the junk yard if you can find one- Rebuild the on you have
Good Luck , Tommy
If Gas was leaking out Exaust manifold I doubt your brother in law would be around to tell you about it-
I am guessing you have an Electronic Q-jet . 3 guesses off top of my head - ALL FROM Experience - Is there black smoke out off the tail pipe (soot) ? Check the check valve on the Charcoal Canister you might be sucking gas right out of carb- /Ground the ALDL -turn ignition on- You should hear a rapid Clicking from the top of carb-if not the mixture controll solinoid is stuck- /
Is it hard to start first thing in morning ? Allmost all Q-jets leak after a few decades from the plugs in the bottom of the float bowl flooding the intake w/gas and emptying the float bowl- And don't forget to see if the float is stuck - If you find someone old enough to know what he's doing he can fix the q-jet (rebuild it in a hour) Don't go buy one fro the junk yard if you can find one- Rebuild the on you have
Good Luck , Tommy
JOEROC
02-15-2004, 03:34 PM
sounds like tommy is on to something. its a comin problem with the Q jet. the only thing he didnt mention is that Q-jet = Q-junk, hahaha.
neves
02-24-2004, 07:36 PM
to help you out >>> there is no fuel in the exhaust manifold to leak out. this is just impossible if the engine is running. you might be in the right area to spot a close by fuel leak. these other guys are also correct in saying that the canister check valve could be defective. hint: check the simple things first. they're usually what is wrong
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