Hi, new to this forum.. Bought a 99 mil 2.3 s with 89km.Had absolutely no problems when i first got it, now it is blowing a large abount of smoke ONLY at startup and only after it has sat for more than an hour or so. PLEASE HELP. If anyone can help please send me any info you have. Thanks Mazda4life

 

Sounds like leaky valve guides to me (the oil drips down the stem of the valve and pools into the combustion chamber, not enough leaks to give you constant smoke, but over time it is enough to give you a good puff at start-up)

To fix youneed to have a cylinder head job done (new valves/guides at a minimum.)

 

Thanks so much for the quick response. Would there be any other symptoms that I should notice with this problem? Some people have told me that bad supercharger gaskets areusually thecause to these same symptoms. Any suggestions to make sure I know exactly what it is, so when I take it into mazda they dont try and tell me its something else. And how much is a valve job? SHould I do anything else while they have the engine apart?? Sorry about all the questions! Its all new to me and the miller cycle is quite different than I thought. Its certainly not a simple car to work on.. Thanks again for your help.

 

a leak down would tell you if the guides are bad, BUT, getting to the rear bank is a chore. you can pull off the black plastic cover that says miller cycle on it, and you will see a rectangular plate. iirc, 4 bolts, and the throttle cable runs right over it. pull that plate off, and you can see the rotors of the compressor. they should be a tan color, and free of oily residue. if they are dark, and oily, then it is a good bet that the seals on the compressor have gone south. blue smoke is oil, black smoke is fuel, and white smoke is coolant. this is very general, since it could be a combination. but any smoke is a sign of beginning problems.

 

So I should check the supercharger and get a leak down test done before going ahead with the valve job? Should I also change the t-belt and water pump at the same time?