Help...p0172 & p0175 codes

[Neox5]

Hey guys...im getting the following codes (P0172 & P0175) after the engine failsafe program comes on. I would turn the key off and wait a few seconds and it would be back to normal but the check engine light would come on. The codes are for the 02 sensors.....but some on the site have said it is the MAF or the engine wiring harness......wouldnt the MAF code come up if it needed to be checked? I have a 2003 X5 3.0

[Neox5]

Anyone?.....i aint taking it to the dealer cause im tired of getting ripped off.

[flyingmachine]

How did you read the codes? Peake?

That's bank 1&2 system too rich. Basically, it means the o2 sensors on bank 1&2 have too little oxygen in exhaust. do you get rough idle? misfire? Try cleaning maf sensor and clear codes. See if codes come back. But if MAF is gone, cleaning might not solve the problem. If you have more advanced ODB2 tool, you can read MAF live data.

Also, it could be a vacuum leak. 2 hoses to oil separator are tend to deteriorate soon. Check if they're gone. It could be just the faulty O2 sensor too but unlikely both are gone at the same time.

[flyingmachine]

Originally Posted by flyingmachine

How did you read the codes? Peake?

That's bank 1&2 system too rich. Basically, it means the o2 sensors on bank 1&2 have too little oxygen in exhaust. do you get rough idle? misfire? Try cleaning maf sensor and clear codes. See if codes come back. But if MAF is gone, cleaning might not solve the problem. If you have more advanced ODB2 tool, you can read MAF live data.

Also, it could be a vacuum leak. 2 hoses to oil separator are tend to deteriorate soon. Check if they're gone. It could be just the faulty O2 sensor too but unlikely both are gone at the same time.

Oh. you have 3.0. Then you can ignore what I mentioned regarding the oil separator hoses.

[Neox5]

my mechanic hooked it up to his computer.....i do get rough idle at times....and i did get a misfire awhile back

do you know of a code reader that can read the MAF live data? thanks

[The Cleaner]

II am on the same page as flyingmachine.

if you get more than one O2 sensor that has a code look upstream for the problem, most O2 sensors don't fail together. If you can, check the voltage to eliminate them. I'd clean the MAF and if that does not solve the problem I'd replace it.

Check intake boots for cracks, I see that on occasion.

[Weasel]

The snap-on scanner and/or modis can get live data. I wish the code readers would give you all the same info as the one at the dealer... If it is adaptive mixture faults it was set at idle. If it is multiplicative faults, that's at higher RPMs while driving. The multiplicative rich mixture faults are usually the MAF sensor. The other thing about the dealers diagnostic software is it will tell you the multiplicative values and you can see after a couple miles if the values change for the better or not... hence, no guessing. (judging its a competent tech, not a newbie kid)