wusup to all H T members..as you can see im brand new to this site..freshly got out of the rotary scene..gave up on the rx7 fc3s..to much maintenance and very expensive parts..so i moved on to a honda...

i bought a 97 honda civic hx with a blown head gasket...got the old head out and took it to a machine shop.they did a valve job,resurface,and a compresion test,
bought all the gaskets i need and even replaced timing belt and the thermostat..
after all work got everything installed..started..and still smokes like a chimney..
i left the car on for a good 30 mins and the smoke went a way...but ive been driving the car for almost 2 weeks now..and everytime i start it up it still looks like it has a blown head gasket..but after a 10-15 mins the smoke goes away..and i change my oil last week and i checked it yesterday and the oil is really dark.
and i just recently passed smog like 3 days ago after driving it for an hour to get the engine warmed up..

do you think its just old left over coolant from the block..or a bad cat or what could it be?

 

bump. i have the same problem.

 

check the NOX levels on your smog certificate, if it is close to the limit , your cat may be bad.

 

MAYBE a leaking valve seal. if the valve stem seal is no good it will leak oil into the combustion chamber while the engine is cold. when the engine warms up the seals expand and seal themselves up. after you turn the motor off and it cools the seals contract again and allow oil to leak into the combustion chamber again, so when you start it up all that oil starts getting burnt and continues until the seals expand again.

only problem is you said it's white smoke. it would probably be blue if it were oil. white smoke usually indicates that there is fuel not being burned. that would be rather strange if it were that because it would probably indicate an open/closed loop confusion in the ecu since it suddenly goes away, one of your sensors might be bad or maybe you have a malfunctioning ecu.

are you sure you are describing the color and the duration of the smoke accurately? compare it to engine temp... check your ecu diagnostics trouble codes too.

 

not to be confusing but coolant in the combustion chamber can produce white smoke but if the motor passed a compression test then it probably isn't coolant... and if there were an open passage to the water jacket then your coolant system would become pressurized and you'd probably have blown the head gasket already by now anyways. I doubt it.

 

thnks for everyones suggestions..ill check up on it as soon as i get off at work or tomorow morning.