Toyota Repair: 1998 Toyota Sienna Van P0125 error, coolant temp, o2 sensors

Question
I have a 1998 Toyota Sienna van.  I have replaced ALL the sensors.  The computer codeswere errased. The van check engine light comes on still and the error code reads Closed Loop Fuel Control, Insufficient Coolant Temp. PO125. The van has been doing something peculiar.  Occassionally it misses or hestitates when you are accellerates, you can push the gas peddle all the way to the floor and then suddenly it stops hesitating and takes off.  There is no consistency at all.  Does it when it is hot or cold, with or without the AC on. Can't figure it out, nor can anyone else. Please let me know what you think.

John

Answer
The O2 sensors are recording a too lean condition on one or both of the cylinder banks, since you stated that it sometimes misses or hesitates I would recommend finding the cause for this condition and repair it to solve this. Are there any other codes? These engines have had some problems with ignition coil packs and fuel injectors but mostly with the coils, there could also be an intake air leak or an exhaust leak, both will set the 125 code. A decent technician should be able to read the freeze frame data on a scantool to see what the engine parameters were when the light was set, I would have them clear the code and then test drive it then recheck for any pending codes or hard fault codes.