my son has a saturn 2008 astra the car runs rough then white smoke out tailpipe it is using oil

I suspect it is using coolant and that coolant it is going out the tailpipe. White dense sweet smelling smoke usually indicates coolant in the exhaust. On some vehicles this coolant can come from the intake manifold leak, but the most common cause is a bad head gasket or cracked cylinder head.

That's unbelievable! You have a Saturn that actually runs? You should call the six o'clock news and let them come out and film it in action, because nobody's going to believe it. In other words, junk it and buy something else.

Run a compression and leak down test and see what is going on with your engine. Most auto parts stores will loan you a compression tester.

first of all I have a 1993 Saturn that gets 32-35 mpg and use no oil it runs like a top. the issue it had is the instructions on how to install piston rings! Second the way rings were installed in the original build. just remember physics does not change from auto manufacture to manufacture. what I am saying is when a manufacture installs something wrong is what caused most of the oil issues that Saturn had. as a note compression rings, the bevel always goes up!!!

figured it out this was blue smoke most likely oil rings, what the son described a white well it was not after a short distance of following him thank you

@ GuruDMBCS- If the second ring has it bevel it may be engineered to point downwards. Always follow the manufacturers instructions when installing piston rings to avoid another teardown.

Fyi 30000 miles later 1993 still runs great no oil usage the rebuild was the ticket. 2008 went a through a rod on the # 1 piston taking outsides of the block, then the oil pan, starter Bendix, oil cooler and to top it off the piston was free. crank was free as well. the intake had oil in it end the story replace the engine Rx Astra runs great, still like Saturns

Pcv valve failure in the valve cover,,cover and gasket needs to be replaced, Oil is being pulled into the engine though the pcv valve when the throttle is closed creates a higher vacume though the pcv allowing oil to enter intake manifold,,this also causing a rich condition due to stray unmetered air entering the engine, bank 1 o2 sensor sees a lean condition then adds more fuel to compensate,,this will show higher long and short term fuel trims (15-35)

@ Ricky - I know this might have been posted 8 months ago but I have looked around online for someone else having the exact issue and to explain to me why and you hit the nail on the head. I just bought the car used for 400$, 2008 Saturn Astra. had to replace the valve cover cause some dumbass cracked it and then decided to use globs of gasket sealer for his amazing repair job. After an hour of cleaning the block and getting all the sealer off and putting the new valve cover back on, I was just trying to find anything that looked abnormal. then i noticed there was a lot of oil residue on the ridges of the intake plastic tubing . i just kinda shrugged it off and went about putting it all together again. I also thought this is why the car felt like it has 0 power what so ever. but after putting it all back together and test driving it stil has ZERO power and I am getting the p0017 DTC... which is the crank/cam sensors, o2 sensor, and a lean system or something. I don't know exactly. I am not a board certified mechanic - but i have worked on my own cars since i was 16 - i understand how an engine works but i would never be able to explain what you just did @ricky, -- thats exactly wtf is happening.... now how do i fix it??? i mean i replaced the valve cover which in turn also replaces the PCV valve on the inside of the valve