I have a 2003 Protege 5 that is burning oil. It goes through about 2 quarts of oil in just under 2 weeks. Every time I start it in the morning or after about 6-8 hours of sitting it blows out blue smoke. We have replaced the PCV valve twice, put on a brand new head with new seals and everything, spark plugs are new, replaced the head gasket and checked the compression on the piston rings. Compression is good. We are stumped as to what else could be the problem. PLEASE HELP!

 

Usually valve stem seals cause a puff of blue smoke when first starting or even when pulling out from a stop.Had a car doing this once and the new valve stem seals fixed it.Only other thing would be bad rings,damged cylinder walls or you may have a oil ring that is stuck in the ring groove which is not unheard of.

 

Since the head and seals are new and the symptom persists it is most likely an oil control ring. Each piston has several rings, usually 2 compression rings and below them a oil control ring that works like a squeegee on the cylinder wall. If that squeegee doesn't touch the wall the oil gets past the compression rings and gets burned. It would make sense because you do have good compression even though you burn oil.
Before ripping the engine apart I would try a fix in the can. For example "Seafoam". Put 1/3 of a can into the oil. It contains the solvent Naphtha and could remove sticky varnish. Follow the instructions on the can. Be aware that it causes a big white plum when you put it into the intake, so don't make your neighbors angry.

It is cheap enough to try your luck.

 

ThAnks for your reply. I just ran the car for a few days without the pcv just in case oil was getting into the cylinders that way. No change. A compression test shows 190-210 in each cylinder. A leaks own test shows 15-22% in each cylinder which is good. I pulled the exhaust manifold off the new head yesterday to inspect it and cylinder 1 was wet with oil in the exhaust port and the collector in the manifold down to the catalytic converter. There is also a pool of oil on top of the piston looking down the spark plug hole. I'm stumped. Any more thoughts would be great. Thanks

 

I think it is a bad piston ring. The new head did not help and there is still oil getting into the combustion chamber.

So I would do one more cheap trick: if the ring is stuck in the groove as newyota suggested then "Seafoam" in the oil could help loosen it. You would have to drive with it for at least 100 miles to clean up the interior of the engine, probably longer in this case.

If that does not help the engine needs to be taken apart.

 

Does it only smoke after start up ? if so I'd be suspicious that a messed up valve guide and/ or seal could have gotten installed.

Seems top me the oil ring would continue to leak and smoke as bad or worse than start up as the car warmed up.

 

Here's some pictures of the motor and head before and after I installed the new head. Same smoking problem . . .

Old head looked like this on cyl 1 exhaust port


Exhaust manifold and gasket was soaked with oil on cyl 1


Carbon Deposits on piston heads




Cleaned deposits and wiped down cylinder walls with brake clean



Old head looked like this . . .




New head next to old




New head exhaust ports



All new gaskets



AND AFTER DRIVING WITH THE NEW HEAD for 1,000 Miles, THIS IS WHAT IT LOOKS LIKE AGAIN!


Cylinder no 1 Exhaust Port and valves (note, small bit of oil dripping down from valve guide - are they supposed to do that a little?)








oil coated in exhaust manifold down to where the cat meets it.

 

I hope the pictures help show what the problem is. I'm about to call if quits and go for a new motor but I don't want to.

At this point anything could be possible. My thoughts are:
1) Possible the seals/guides are bad again in the new head (but not likely. I grabbed the valve with pliers through the exhaust port and I didn't feel any play)
2) there is a small crack in the oil galley from the block to the head leaking oil into the cylinder (thus causing the same problem regardless of old or new head)
3) the oil ring on the piston is bad (even though compression is ~200PSI in all cylinders)

When I bought this car it didn't seem to smoke at all for the first week or two, until I changed the oil and filter in it myself (because I figured it should be done not knowing last time it was changed)

Used a fram filter and 4 quarts syn blend valvoline 5w-30.

I noticed that it did have a genuine Mazda parts filter on it ( which shows the owner took good care of it and the carfax showed it went to the dealership every 3k miles for a oil change)

Right after the oil change it started smoking. We noticed it in the morning after it's sat overnight, or if the car has sat for 6-8 hours or longer. But if it's driven and then only sat for 1-4 hours it starts right up and it won't smoke.

It hesitates real bad between 2-5k rpms, almost no power. It feels as if I'm towing a 3,000lb trailer behind me. I have to floor it to get me and 3 passengers up to speed while merging on the freeway, and it takes about 12-15 seconds to get up to 65.


Any valid opinions are welcome. There's a guy on the mazdas247 site that had this exact same problem 2 years ago, but I haven't been able to get a hold of him.

2002 P5 smoking, burning oil, rough idle......

 

In my opinion it is 3) the oil ring on the piston is bad.

The oil ring does not contribute to compression. It is a squeegee for the oil. My brother once rebuilt a motorcycle engine and he mounted the oil ring upside down. That ring was pushing the oil up rather than down. Oil consumption was way up and compression was fine.
Other than that my brother is a smart guy.

You can clean up the old head and sell it.

 

You beat me to it; I was going to say essentially the same thing.

Regarding a microscopic crack in the block; while not impossible, it is highly-highly improbable.