02 sensor problem

[az564]

I have a 986 boxster 2.5 it had 4 codes to do with 02 sensors bank 1+2 ahead of cats so I replaced with universal 4 wire sensors now I have 2 codes p0130 + p0150 02 sensors ahead of cats signal implausible checked for air leaks. It runs rough on idle and when revs drop when slowing down it cuts out. Any ideas? Thanks aarron

[JFP in PA]

I have a 986 boxster 2.5 it had 4 codes to do with 02 sensors bank 1+2 ahead of cats so I replaced with universal 4 wire sensors now I have 2 codes p0130 + p0150 02 sensors ahead of cats signal implausible checked for air leaks. It runs rough on idle and when revs drop when slowing down it cuts out. Any ideas? Thanks aarron

 

Both codes can also be caused by wiring problems, and as you used "universal" fit sensors, I would start there.   I would also have to say that we never use this type of sensor in the shop both because of the probability of having this type of issue, and because the correct fit units do not cost that much more.

[mikefocke]

You may want to use Bosch O2 parts, not universal and not Porsche. You do want to use ones with factory crimped pigtails. Not soldered.

 

A list of the parts Porsche buys from Bosch is here. http://sites.google.com/site/mikefocke2/oxygensensors

[az564]

Today I replaced the 02 sensors with some direct fit not universal and still have the same problem

[JFP in PA]

Today I replaced the 02 sensors with some direct fit not universal and still have the same problem

 

The codes you are throwing P0130 and P0150 are both short circuit codes, indicating a problem in the wiring for the sensors.  Nearly every time we get a car in with universal sensors throwing these codes, it has to do with the way the wiring was connected to make the aftermarket sensors fit and work.  At this juncture, you need to start tracing the sensor harnesses and checking each of the individual sensor leads for a short or break using a multimeter.  I would also can the harness looking for any damage (burnt by heat, abraded, insulation cut, etc.)

[az564]

Ok thanks will check tomorrow is there an ecu that would control the o2 sensors

Edited May 26, 2015 by az564

[RFM]

The sensors are controlled by the DME, since they are an integral part of the engine management.

[mikefocke]

You say "direct fit".  A term I'm not familiar with. Can you cite a part number and brand you used? Maybe give a net reference?

[az564]

They were fme but had factory crimped plugs on I have checked wires and all look ok so think it must be something like the dme. Does anyone know what one it is? Or anything else it could be

[Schnell Gelb]

Az564

Your codes mean there is a short circuit. Surprising that it is in both banks simultaneously. That may mean the wiring fault is some distance away from the O2 sensors ? You need to use a wiring diagram or physically trace the wires back from the O2 sensor all the way to the DME to find the short circuit.

This is tedious,slow work with a multi-meter. Throwing parts at it won't help.Muddling the connections for each sensor would also cause a problem.

Start by asking for a link to a wiring diagram?

Here is a useful article:

http://www.pelicanparts.com/techarticles/Boxster_Tech/19-FUEL-02_Sensor/19-FUEL-02_Sensor.htm

Here are the correct parts :

http://www.pelicanparts.com/cgi-bin/supertech/catalog.cgi?action=frameset&return-url=/cgi-bin/supertech/catalog.cgi%3Faction%3Dframeback%26page%3D526&catalog-url=http%3A%2F%2Fwww.pelicanparts.com%2Fcatalog%2FSuperCat%2F1048%2FPOR_1048_FULEMI_pg1.htm%3Futm_source%3DSuperTech%23item0

Hope this helps you.

[Ahsai]

The quickest way is to get a scanner that can read the O2 sensor voltage (any generic OBDII will do). Watch the signals of all 4 sensors so you can see what the DME sees and doesn't like about.

[mikefocke]

Could some rodent have gotten into the wiring harness?

 

Is the car completely original/OEM/stock? What recent work/changes have been done?  What sensor parts are now installed (part number)? Air filter?  Exhaust? Any sign of an AOS problem?

[az564]

What ecu or dme would control the o2 sensors and where are they

[JFP in PA]

What ecu or dme would control the o2 sensors and where are they

The DME should be in your rear boot, behind a trim panel.

 

[ARModen]

First question is, are the codes you had before you replaced the sensors different than the codes you have now.  It sounds like you've replaced the sensors twice and still have the original problem.  If you have a short circuit in the cable between the ecu and the plug for the O2 sensors, then replacing sensors won't do any good.  The cables go around the exhaust and up to the DME, so the most likely thing is that they have come in contact with something hot that has melted the insulation off and shorted them together.  The other possibility is that they are pinched inbetween suspension or engine mount parts.  I'd get it up on a lift and get a flash light and take a look at the harnesses going back up into the car above where the sensors plug into them.  I'd guess they go straight up and then over to the driver's side and into a bundle going back to the DME in the trunk.

[az564]

The codes I had before were p0151 p0131 p1115 p1119 all 02 ahead of cats