Losiho

My 95 LS400 with 140,000km on the clock (87,000miles) suffered the same low and rough idle symptoms that many on this board appear to have had. I made a note of it to my Lexus dealer who just completed the 140,000km service, and asked them to check the TPS, throttle body, IAC and MAF. They could not fault any of those, and the OBD reader pulled no codes. They said the low/rough idle could be caused by carbon build up in the throttle body and fuel injectors, so a full carbon flush and clean of the injectors and TB was done.

The car has transformed after service. It no longer has a low idle, and it also revs much more smoothly and "quickly". Good to see that a quick clean cured all of the problems