Yo. I was referred to this forum though a buddy who says you all know your stuff. My car has a stock s15 sr20. It's always burned a bit of oil on deceleration, but it started getting much worse towards the end of summer. I usually like to downshift through the gears as I'm slowing down and every once in a while it would make a big puff of smoke out when i grab a gear on decel. It clearly smelled like burnt oil. I didn't notice anything on accel. The car runs fine, makes normal power. Doesn't smoke or smell like burning oil at idle or on start up. It does have some intermittent surging at idle but I'm pretty confident that's unrelated, probably TPS or something. It's been in storage for winter but i decided to run a compression test today. I let it warm up to temp, didn't smoke or smell burnt oil while idling in the garage. Results were 148, 148, 105, 148. When i pulled the spark plugs, all 4 where a nice golden brown color at the tip. Coolant is clean and clear. Only thing I can think of is something with valves. Any other ideas or things i can test?
Do another compression test but first put a teaspoon or so 's worth of oil down the plug hole. If the compression readings dramatically improve then it suggests the problem is ring related rather than valve.
Breathers clear? Pcv blocked? If all is good there I would be looking at valve stems. Pull the exhaust mani off and see if it's wet and oily stems
When did valve stems cause low compression? As tinker says you now need to do a leak down test! And start listening to where the leak comes from! Also as inliner says do the oiles compression test to check if it's Pistons/rings.
