White smoke from tailpipes/ Please help/Running out of ideas

erniet17

Member
Oct 4, 2005
124
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Hey all. We just purchased a 1991 vert. On some occassions, when you crank the car in the morning, it will let out white smoke and the car has a huge misfire. It smells like raw gas. So far we have changed the coil, cap, rotor, cables, plugs, mass air and removed the cats. It's also been through a few tanks of gas. What can this be? I'm assuming that if it were to be a head gasket it would do it at all times. It might do it when the car is on the highway at normal operating temperature. I would appreciate any and all feddback regarding this issue. Thanks
 
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How many miles on the car? My 87' GT started this last month but I sorta expected it soon because it starts with the engine burning oil. The valve seals in the heads need to be replaced.

Good excuse to buy new parts!
 
It doesn't do it all the time. It smells like raw gas, misfires/sputters and a ton of white smoke coming out the pipes. It doesn't smell like burnt oil. I am going to try and take a picture of it when it does it again. It smokes almost as bad as when you use seafoam.
 
Well if you remove the cats, you are always gonna have a little smoke and the raw fuel smell.

Did it do it before removing the cats?

Run a compression test to check if a HG popped
 
It doesn't do it all the time. It smells like raw gas, misfires/sputters and a ton of white smoke coming out the pipes. It doesn't smell like burnt oil. I am going to try and take a picture of it when it does it again. It smokes almost as bad as when you use seafoam.

that isn't normal. maybe head gasket? as in above check oil and compression check. if it is milky then you have a cracked head gasket.
 
It did the same thing with the cats on. The oil looks good. Haven't noticed anything in it. If it was to be the head gasket, wouldn't it do it all the time? Or do you think that once the thermostat opens it rushes water into the jacket and into the cylinder? I am going to have the mechanic run a compression test. Thank you all for your responses.
 
Do a pressure test on your coolant system too. That much smoke being white, you've got water. So much so that it's preventing ignition in one or more cylinders, so therefore you're smelling raw gas too.
 
Let's say that it is a head gasket. Wouldn't the car smoke all the time. It's intermittent. My mechanic thought it was a sticking injector but he says it's not. Now he's checking the computer and ECT. I don't know what the ECT would cause but he said it is possible. The car has been in the shop 4 days and no one can figure it out. It's probably something stupid.
 
Let's say that it is a head gasket. Wouldn't the car smoke all the time. It's intermittent. My mechanic thought it was a sticking injector but he says it's not. Now he's checking the computer and ECT. I don't know what the ECT would cause but he said it is possible. The car has been in the shop 4 days and no one can figure it out. It's probably something stupid.

Yes it could be because with heat and metal expansion, although rare, you can have a headgasket that only leaks when the expansion/contraction makes things shift "just so".
However, that's really really unlikely.

There are more ways for coolant to get in your chamber than a headgasket. It can enter through the lower intake manifold gasket to head, and also through the EGR spacer/throttle body.
 
The car will mostly do this when it is cold. First thing in the morning. The coolant lines to the throttle body spacer are disconnected. The mechanic pulled plug #1 out when it began running crappy annd the plug was black. He's thinking something electrical.