I disagree. Burning oil on a high mileage engine is normal especially at high revs. The shuddering only happened that one time. I have not seen it since. The engine runs fine except at higher revs under load which I have not been able to reproduce. Engine would not run normally with a broken piston. My money is on worn plugs and/or coil packs.

Don't forget that the PCV valve can also effect the oil consumption....

Yes, PCV valve was replaced 12,000 miles ago.....it was original and suprisingly was not blocked and didn't look bad for its age....

So I have not made any repairs to the ignition system since the original problem (see above) as the car has been running fine. I have 70k on my iridium spark plugs and the coil packs are original. So I'm getting on the highway the other day and bring the car up to 4k. The engine sounds fine and accelerates with no hesitation or loss of power, no visible smoke from the tailpipe, but my check engine light flashes. So I am wondering if the CEL only flashes during an engine misfire and if so, how can I diagnose what the problem is. With 70k on my plugs, I would not be surprised if that is the issue and with original coil packs @ 270k, I wouldn't be surprised if that is the issue. Would the computer show a code for a bad coil pack or should I just go ahead and replace the plugs and coil packs?? All comments are appreciated.....