What do these Toyota OBD codes mean?

Question

This question will likely require the experience of an up-to-date Toyota Mechanic.

I have a 1999 Toyota Sienna V-6. It runs fine but It's On Board Diagnostics computer was tested for it's annual vehicle inspection, which now includes emissions in the state of NH.

There were error codes that came up, however the garage doing it didn't know much about toyotas so they said those were proprietary dealer codes. They are as follows:

P0125 which did say was "Insufficent Coolant Temp. for Closed Loop Fuel Control"

P1130 no Description

P1135 no Description

P0300 Random/Multiple Cylinder Misfire Detected

P0301 Cylinder 1 Misfire Detected

P0303 Cylinder 3 Misfire Detected

P0305 Cylinder 5 Misfire Detected

These likely indicate a sensor malfunction is my guess, but which one and where? What must I do to make these codes go away? I really can't afford to pay the dealer to work on this vehicle. I am capable of most mechanical repairs. If someone with an accurate understanding would be good enough to share their knowledge it would be much appreciated.

Answer 1

P1130 is Air/Fuel Sensor Circuit Range/Performance

P1135 is Air/Fuel sensor Heater Circuit

these are because cylinders 1,3,and 5 are not firing which also causes code P0125 .These cylinders are not making heat. the P0300 is because 1,3,and 5 dont miss constantly but they do frequently hence 301,303,and 305. P codes are for Powertrain. I would give the vehicle a good tuneup and make sure you are firing on all cylinders. Possibly need new O2 sensors if those codes don't go away(1130 & 1135) The definitions you DO have are correct. The P0125 "closed loop fuel control" thing is referring about your vehicle no longer being in "warm up" mode. In warm up mode you vehicle does not rely on sensors, it just follows default values for a specific length of time to warm up the engine, then it will adjust everything according to the sensors's inputs to the computer on the vehicle

Answer 2

1130 and 1135 deal with the air/fuel sensor on bank 1 as the rest of the codes justify. misfire on every cylinder for bank 1. p0125 indicates a possible thermostat failure. p1130& p1135 indicate a sensor unplugged or failing. the rest will likely clear with the repairs indicated