1990 LS400 Code 13

[mrm]

I am the sole owner of a 1990 LS400. Last November, at 131,000 miles, I had an experienced local mechanic change the timing belt and water pump. He purchased a kit (not from a dealer) that included the idlers and tensioner. When I picked up the car, the check engine light (cel) stayed on and the famous Code 13 was displayed. He kept the car and discovered the crank was off by 2 teeth and he corrected his error. When I picked up the car the second time, the cel came on about 10 seconds after start and went out after about another 10 seconds. There were no other symptoms. I have been able to retreive code 13 and clear it on many occasions. Sometimes the cel will stay on for an extended period, but a shut down and restart always keeps it off for that particular trip. He has had the car back for a timing inspection and checked the resistances and wiring on all three sensors. No cause has been identified and performance is fine.
Does anyone have any suggestions or a similar experience?

 

[Lextreme II]

check the oxygen sensors....or perhaps cats.

 

[sideshow]

13 is timning out get him to recheck
if he has fukt it b4 then good chance he fukt it agian