93 LS400 (75-80,000 miles) driving normal at highway speeds, hickuped once, then began running rough, very rich (stinks, one or both cats hot, and some black smoke out tailpipe when accellerating), barely idles, and the check engine light is on. I followed the proceedure carefully for reading codes (not my first rodeo) but get no blinks at all - no continuous blinking indicating no codes and nothing indicating a particular code. My first thought was the TB but it was replaced less than 15000 miles ago by the dealer.
Here is where it gets odd - once this condition presented, the car would not put itself into 1st gear. I can manually shift to 1st, but it was trying to leave from a stop in 2nd or 3rd.
Car did same thing yesterday pulling out of a gas station (fill up), after a fairly long in-town drive in hot weather. CEL was on. Wife wisely left car in parking lot and we went back (to the soccer tournament) this am. I checked codes and got the steady blink indicating no codes (I can't even get that now). One confusing issue was a courtesy light was on all night so the battery was amost dead, had to jump it off. But it ran fine until the repeat event coming home from the tournament.
While I realise this could be many things, I find the inability to read the codes odd. Also I hope the sudden onset might be a big clue for someone out there.
Thanks in advance :o
