I own 4 Toyotas and one Lexus (too many kids) and the Lexus just threw me for a loop.
'94 Lexus ES300 with 168,000 miles suddenly stalled while stopped at a light. Rolled to the side and tried to start it but no luck. All the dash board lights light up like normal so power was there to the gauges and starter motor. Waited about 5 minutes and it started fine with no check engine light. Hooked up my OBDII laptop and there are no diagnostic codes or problems recorded.
O2 sensor readings: One looks funny. O2 sensors B1 S1 and B2 S1 plots look fine with sensor voltage (or current) and fuel trim or lambda both going through a sine wave dance. Fuel trim staying between 0 and 4. O2 sensor B1 S2 looks funny: sensor voltage (or current) on the low side and fuel trim or lambda is pegged at 100. I didn't know this thing had 3 O2 sensors (at least that's what my computer is trying to tell me).
There has been an intermittent trouble code about every 7 months of P0300, P0301 & P0303 (Random/Multiple Cylinder Misfire Detected, cylinders
1 & 3) but no hesitation or performance issues when it happens. I just clear the codes and wait for it to come back.I'm starting to study the service manual but I'm having trouble figuring out where to start without some kind of diagnostic code.
Paul. Phoenix, AZ