When it rains it pours... Last night I took the 240 with 275,000 miles for a shake down cruise after replacing the driveshaft. Coming off the exit, I noticed sparks flying out of the tail pipe. Although there was no signs of backfiring, I did notice a very slight miss coming from one of the cylinders during the cruise.
I suspect these issues are the result of running late for work one day last month. Definitely not because I was also running with the pack at times exceeding 90 mph in the left lane.
That day pulling into the company parking lot and later limping home, I did notice the motor was idling a little rough but I was too preoccupied by the bad vibration and clanking coming from the rear axle to take notice.
Is it possible that I floated a valve? I do have a lockup transmission so I doubt that it was over revved. I believe doing a compression test would be one of the first steps. Perhaps starting a list of the likely culprits to tackle next weekend would also be where to start. I suspect driving it will damage the O2 sensor and the year old OEM exhaust system. So it will remained parked until it's repaired hopefully before winter. But first should I try some of the additives?
Ten miles of having fun is beginning to sound awfully costly.