Bunch of Codes...New catalytic converter?

[cca6164]

Hi all, long time reader of the forums...first time posting. I have a 2006 X5 3.0 throwing 5 different codes: P0313, P1092, P0135, P0420, and P0430. I was aware of some emissions issues, but have been pushing them off until now…months before inspection of course. From my brief research on the forums it appears it could be a combination of a failing catalytic converter and o2 sensors. I have such an array of codes I thought a new post would be more sufficient than trying to piece together other peoples issues. If I need to replace a catalytic converter how do I know if it’s the front one or the rear one? Is the misfire related to the lean code? Exhaust/emissions isn’t my strongest area of knowledge so dumb it down for me please. I figured the first step would be replacing all 4 of the relatively cheap o2 sensors. Those are ordered and should be installed next week. Any other help is greatly appreciated!

P0313: Misfire detected with low fuel
P1092: Pre catalyst fuel trim system too lean bank 2
P0135: o2 sensor heater circuit bank 1 sensor 1
P0420: Catalyst system efficiency below threshold bank 1
P0430: Catalyst system efficiency below threshold bank 2

[cca6164]

bump...anyone?

[chedeng]

It looks like P0313 and P1092 are for both LEAN conditions. P0135 is O2 sensor heater circuit. Since you already bought O2 sensors (pre-cats), might as well install them and go from there.


The LEAN codes could be anything from vacuum leak, bad fuel pump, bad injectors to bad MAF.


vacuum leak - unmetered air getting into the engine causing LEAN (less fuel). Check vacuum hoses, intake, etc. Make sure clamps are tight. You may need to "smoke" test to pinpoint the leak(s). There's a lot of videos showing homemade smoke device.



bad fuel pump - not delivering enough pressure and flow. You will need a pressure gauge hooked up to fuel rail. Reading should be 44psi - 50psi range.


Bad injectors - clogged injectors and need to be cleaned?


MAF - expensive little bugger. Make sure clean it first with MAF sensor cleaner that you can get from local automotive store



Now, the post-cat O2 sensors monitor catalytic converter efficiencies. The codes P0420 and P0430 are both catalytic converter inefficiencies. These codes don't have anything to do with the other three. It could be the end result not the cause of the three codes.Try getting rid of the first three codes first before tackling P0420 and P0430.



I replaced both of my catalytic converters on my car three months ago since it was due for inspection and would not pass NY emissions. I did not have any codes except for these P0420 and P0430 that will come up after a few miles of driving. I have had the luxury of driving the car with these codes coming on so had time to troubleshoot that both cats are bad. Not cheap though. I bought an aftermarket Eastern Catalytic ($750 for both) and installed it myself. It is a difficult process so if you are not handy and do not have access to basic tools, I suggest have a mechanic do it.

[srmmmm]

Don't forget the fuel filter. You can still have the correct fuel pressure showing at idle, but may not have sufficient flow under load.


Avoid fuel additives and stay with tier 1 fuels. I traditionally only run Shell gasoline and have only replaced two O2 sensors in 344,000 miles and still have the original convertors.


2002 X5 3.0 344,000 miles
2014 428i 39,000 miles


2004 325i sold at 123,600 miles
2001 325i sold at 66,000 miles


1970 Firebird Under restoration

[cca6164]

Thank you both for your help. Update after cleaning the MAF, air filter and replacing all four o2 sensors. Was code free for 90 miles until it threw an old code and a new one.
P1092:Pre catalyst fuel trim system too lean bank 2
P1093:Pre catalyst fuel trim system too rich bank 2
Not sure if its purely mental, but car seems to be running happier. Those o2 sensors looked really beat up, wouldn't be surprised if they were original. I am thinking of tackling the fuel filter next. Or should these new codes be pointing me in a different direction? Thanks!

[chedeng]

Originally Posted by cca6164

Thank you both for your help. Update after cleaning the MAF, air filter and replacing all four o2 sensors. Was code free for 90 miles until it threw an old code and a new one.
P1092:Pre catalyst fuel trim system too lean bank 2
P1093:Pre catalyst fuel trim system too rich bank 2
Not sure if its purely mental, but car seems to be running happier. Those o2 sensors looked really beat up, wouldn't be surprised if they were original. I am thinking of tackling the fuel filter next. Or should these new codes be pointing me in a different direction? Thanks!

Hmmm, the two codes P1092 and P1093 contradict each other. Can't have both; either LEAN or RICH. Could be bad connections to the MAF or O2 sensor for Bank 2.

One thing you can check is the connector for the MAF. Mine if not seated properly gets too rich. If I kind of push the connector on the MAF, the reading corrects itself but after a while it somehow loses contact with pins and could see abnormal readings.

Do you have access to see real time data? More specifically the fuel trims; Short Term (STFT) and Long Term (LTFT). Try investing on a WiFi bluetooth OBD and then download OBD Fusion or Torque Pro.


Here is the WiFi OBD i use: https://www.amazon.com/Veepeak-Scann.../dp/B00WPW6BAE


OBD Fusion or Torque Pro can be downloaded from AppStore. I personally use OBD Fusion but it is your choice. I think I paid $10 for the OBD Fusion.


Looking at the fuel trims will give you a big picture on what's the engine is doing. There are few more PIDs you can see like batt voltage, coolant temp, speed, rpm, cat converter efficientcy etc. so it has more use.