Originally Posted by gazi
I just joined Planet-9 and I have found a lot of helpful information on Porsche Cayman. I just bought a used 2006 Porsche Cayman S with about 49k miles on it. I really like the car and I enjoyed driving it.
Unfortunately, not too long after I purchased the car, the CEL came on. I managed to pull the following codes:
P0037 HO2S Heater Control Circuit Low (Bank 1, Sensor 2)
P0057 HO2S Heater Control Circuit Low (Bank 2, Sensor 2)
P0031 HO2S Heater Control Circuit Low (Bank 1, Sensor 1)
P0051 HO2S Heater Control Circuit Low (Bank 2, Sensor 1)
I checked the fuse box and the 25 amp fuse on row D F6 which governs the oxygen sensor and heater for both before and after the catalytic converter was blown. I replaced it and immediately upon startup, the fuse blew again. So, there must be some overload on the current through that fuse.
Does anybody has any similar experience? Could anybody offer any insight to the problem? Does it sound like I need to replace all 4 O2 sensors? If so, please recommend a good place to purchase these parts.
Thanks for all your help. Any feedback and direction is greatly appreciated.
There are several places that sell sensors, if you do not want to buy from your local Porsche dealer parts department.
Pelican Parts and Sun Coast (or Suncoast
) are two that (admittedly barely) come to mind.
Generally an O2 sensor heater fails with a break in the circuit that results in the sensor running cold and cold the sensor will not work right.
To have a sensor fail with some kind of short...
When you remove the old sensors check very carefully the sensor connector and the wiring harness connector for any signs of bent/broken pins/sockets.
Carefully trace the wiring of the sensor looking to see if a wiring lead was making contact with a hot exhaust pipe or a wiring lead retainer has gone missing and allowed the wiring lead to rub or chaff and wear the insulation off.
Before you connect the new sensors you might want to replace the fuse and see if it blows with no sensors connected. It is rare but the problem might be with the DME, or between the sensor connectors and the DME, IOWs the wriing harness that runs from the connnectors to the DME (located against the forward bulkhead of the rear trunk, IIRC.
Handle the new sensors with care! Do not touch the tips! Avoid using any thread lube that is not specially formulated for use with O2 sensors.
IIRC, when I bought sensors from the dealer the threads already had a light coating of something on them. I never used any thread lube.