ok so my car WAS running fine and then it started misfiring.. only my 3rd cylinder was misfiring.. so i changed out all 6 of my spark plugs and these are the codes that im getting now along with my CEL flashing when starting up the car!

o2 sensor problems :
P0131 Oxygen Sensor Ahead of Catalytic Converter (Cylinders 1 - 3) - Signal Wire Short Circuit to
P0137 Oxygen Sensor After Catalytic Converter (Cylinders 1 - 3) - Signal Wire Short Circuit to Ground or Incorrect
P0151 Oxygen Sensor Ahead of Catalytic Converter (Cylinders 4 - 6) - Signal Wire Short Circuit to
P0157 Oxygen Sensor After Catalytic Converter (Cylinders 4 - 6) - Signal Wire Short Circuit to Ground or In -

o2 sensors problems :
P1117 Oxygen Sensor Heating 1 After Catalytic Converter - Below Lower Limit
P1121 Oxygen Sensor Heating 2 After Catalytic Converter - Below Lower Limit
P1124 Oxygen Sensing Adaptation Area 1 (Cylinders 1 - 3) - Rich Threshold
P1128 Oxygen Sensing Adaptation Area 2 (Cylinders 1 - 3) - Rich Threshold
P1125 Oxygen Sensing Adaptation Area 1 (Cylinders 4 - 6) - Lean Threshold
P1130 Oxygen Sensing Adaptation Area 2 (Cylinders 4 - 6) - Rich Threshold

misfiring problems :
P0300 Misfire Damaging to Catalytic Converter
P0301 Misfire, Cylinder 1, Damaging to Catalytic Converter
P0302 Misfire, Cylinder 2, Damaging to Catalytic Converter
P0303 Misfire, Cylinder 3, Damaging to Catalytic Converter

please help if your firmiliar with this! trying to see if i just need 4 new o2 sensors or should i bring it to barrier and have them take a look at it and end up costing me both arms and legs! thanks in advance!

-ken

 

The Misfire problems are a result of your post cat O2 sensors simply not working, as are the lean/rich error messages.

It seems like you're having trouble with your post cat O2 sensors. Check the fuse(s) for them, as it's odd that they would both fail at the same time.

If the fuse is good, you're going to want to replace the post cat O2 sensors, clear the codes and take it for a drive and see what codes come back.

 

ken,
sorry to hear about your box-star! =( i hope everything works out okay for you. i wish that i could give you advice! mitchel is good!

 

See also "stupid pet tricks" situation like mine where I'd get CEL's and people would aay it was anything from lazy sensors to coil packs. Problem was that the car ran GREAT and without the usual stumbling idle and etc. that would accompany these codes. Yes check the diodes and replace them (cheap) if necessary. In my case??? What was it??? LOOSE gas cap-- I never tightened it too much and the loss of vaccuum was causing the CEL's -- A hard twist of the wrist and I have not seen another CEL in 9 mos. Hilarious.

 

Sounds like the O2's are bad, or it's a coolant temp sensor. What troubles is me is all the banks are showing the code, it's unusual for all the o2's to crap out like this at once.

You might want to disconnect all the O2's & see if they are getting power, & also make sure they are all plugged in right & there isn't a short some where.

Misfires can also be caused by failing coil packs, but I don't think yours are shot.

 

barrier originally told me the 3rd cylinder was the only one that was misfiring.. i changed out all 6 spark plugs and this was my outcome. im gonna go back there and pick up 4 new o2 sensors tomorrow when i get the chance and see what happens after that.. i will keep you guys updated and thank you for all the input and help

 

Not sure if it applies to p-cars but any time I see this in another car after replacing plugs/wires/o2 sensors, we would need to clear the ecu via scanner and let the car run idle for 5 minutes to re-learn its current config. Afterwards, drive it like you normally do for the next half a tank of gas. Again, not sure if it applies to you but it's food for thought.

Hopefully you have a cheap fix heading your way I think i've paid more for repairs on my A4 at Barrier than it was worth from the start. lol.

 

with OBD2, when the car misfires, it should automatically reset the LTFT, it may take a day or 2 depending onhow much you drive it to fully adjust the long term fuel trim.

Don't buy 4 new O2 sensors, just buy the pre cat ones. They are the only ones that have to do with your air fuel ratio.

Sorry, I meant to say Pre-Cat O2 sensors from the beginning, meaning the O2 sensors before the catalytic converter. They have a say in your A/F's, the post cat O2 sensors are behind the catalytic converter and they're only there for emissions, they don't do anything to your A/F's.

Step 1. Buy 2 Pre-Cat O2 Sensors.
Step 2. Install them.
Step 3. Clear the Codes
Step 4. Go for a drive.

Also,

Since this started happening even more when you changed out your plugs,make sure that they're gapped properly, it shouldn't be an issue as they should be properly gapped out of the box, but you never know.

 

Tell Kevin the parts guy at barrier to make sure you get the direct plug in O2 sensor. The plug is often the cause not the O2 sensor itself. Also before you do that go to Schucks or if you are near Maple Valley you can use my OBII scanner to clear the codes. My Boxster had a Misfire once due to what I feel was the junk premium gas that I purchased. I cleard the codes then never recieved it again. I can always help as I have been through more S#IT with my cra then one person ever deserves but I have a new trick comming down the pipeline.

 

i took apart all 4 of my o2 sensors and all 4 are geniric universal ones from schucks!

the pre-cats are the ones where you have to rewire to connect it to the plugs which looks like there fine and the post-cat's are spliced and taped up! previous owner of this car did not take very good care of the car and now im payin for it.. all 4 senors are built up with black smog/dust from the car running very rich. should i just dispose of them or is there any way of tellin if they are still good or not? also how would i clean them without damaging them if they are still usable.

 

Replace them while you're down there.

The post cats only throw check engine lights for emission reasons, they have nothing to do with your A/F's or performance.

 

i dont think my cars able to make it out there.. im down by southcenter mall area and its some what far.. and im trying to avoid towing it out there cause my cars to low, gotta remove bumper to tow it and its gonna be extra money out of my pocket! kinda broke right now.. haha trying to not spend as much as possible.

 

how much are the oem o2 sensors BTW?!

 

here you go

http://www.pelicanparts.com/catalog/..._pg2.htm#item6

 

wow its only 120 a piece on pelicanparts and barrier was trying to charge me 288 a piece for them! thanks bruce.. you just saved me like 6-700 bucks! i hope this would do the trick and get her back up and running in time for the next meet

*crossing fingers*