Originally Posted by schmallz
I'm throwing p1152, and only p1152(and p1000) i've swapped the o2 sensor from side to side, changed nothing. So i then decided to take the car down to JBA in San Diego.
They have tested the wiring harness and even managed to hook up the o2 sensor directly to the ECU. Still acted funny. The heater core in the o2 sensor isn't heating up for what ever reason. After a full day of testing and diagnosis, they still are at a complete loss for what is going on.
It idles fine when I start it up, but when I start crusing in 3rd gear or higher it will sputter as the short term FT slowly climps to 1.250(I can watch this on my tuner)
Sorry I missed this--the OČ sensor heaters are all connected to the same +12V source, the same source that powers the EVAP stuff, and switched to ground via MOSFET transistors in the PCM.
If the heater is not being powered as it should then there is a wiring problem with the +12 V source or the switched ground wire running back to the PCM--or, sit down for this, the MOSFET in the PCM is blown.
Here is a kludgy sort of test/solution. Get an older 4-wire OČ sensor with a 6.0 Ω heater; on our stock sensors the heater is 3.3 Ω, more about this in a bit. The Bosch 13275 is a good pick as it was used on a bunch of mid-90s cars and is usually cheap--$25 to $30
The 3.3 Ω heaters cannot be continuously powered without burning up, however the older 6.0 Ω units can be--so installed the older sensor with the sensor output wires connected normally, but with the heater wires connected to ground and a switched (HOT in run) +12 V source that can supply at least 3 A.
This will result in a functioning, continuously heated OČ sensor that will make the PCM happy...