I changed the oil on my wife’s Mazda3 today and it went off (as such a straight forward task is expected to) without a hitch. FWIW this is the first time I’ve done an oil change on her car. Just to note the steps, I drained the oil completely (it was filthy), removed the oil filter, replaced it with a new one, then added 4.5 quarts of 5W-20 as the manual recommends. When I went to drive the car afterward, though, it was sputtering a little as I drove it around the block, revving too much as I accelerated. By the time I started turning back, smoke was coming out of the rear tailpipe.
When I got back to my garage, I checked the oil level via the dipstick. It was like 2" ABOVE the max oil mark. Bizarre. If it was reading high, I thought I’d try to drain some oil out until it got to the right level. So I carefully took the drain plug out and oil started coming out at a very slow rate which was weird. I even took the oil cap off thinking maybe that would help it drain, but only about 0.5-1.0 quarts would drain before it started trickling. Totally bizarre. I then checked the dipstick to see if that did anything and it was still way above the max mark.
It would seem that there is some sort of blockage causing the oil to read high from the dipstick, but the oil pan seems to be empty. Any thoughts as to what could be causing this and a solution? I’m also wondering if I got a defective filter (which I confirmed after the failed oil change is the correct one).