hi guys have a magna 94 with 2.6l engine

the cars was smoking orginaly with you first started the car and increased as you rev it

so i pulled off the head and seen the head was worn and corroded but head gasket looked ok no signs or traces or leaks.

i got another head from another magna that had done 160km didn't get it plained as i cheak it tolarance and was ok reseated the valves and installed new valve seals put engine backtogeather with new head gasket and is running

now when i first start the car no signs of smoke or anything even if i rev it but after 5 min of idaling then i get white smoke coming from the exsaust give it a rev goes away then will come back.

im stumped on what it can be maybe a sensor or somthing. if it was a gasket or crack it would start smoking straight away.

other thing is themostate is stuck open will this cause it.

any suggestions be great

Normal for a car to blow white smoke from the exhaust, hot moist air from the exhaust hits cold air and you see STEAM. Drive the car for a while to heat up the exhaust system and the steam should be gone. Keep an eye on it, and look for loss of coolant or water in the oil.

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