engine codes 1998 -BMW 328i

[micinnj]

Hello -------I had check engine light on and these codes came up on my Action code reader ,po 170 bank 1 trim malfunction ,po 173 bank 2 fuel trim malfunction-------[these codes don't clear] I don't understand what these codes mean ?------------------------------------------------the following codes came up as well but I cleared them --po 1189 fuel air metering control ,po 1188 air metering controll , po420 catalyst malfuction bank 1 --, po 455 controll system leak ,po 430 bank 2 cat below threshold ---------------------------------------------------------------I think 170 and 173 are main things wrong ,455 says theres a vaccum leak,the 1189 is that map sensor maybe dirty? anybody can explain this to me ? ......................one last think the airbag light is on any way to turn this off ? thankyou.......................................... ..................................................

[Manolito]

If the codes won't clear, then your code reader is not fully compatible with the car. All codes should clear and not come back until the car has been running for a at least a half-minute or so.

How old are your oxygen sensors? The maintenance schedule says to replace them every 90k miles, and my experience with two high-mileage '97s in the driveway is that the maintenance schedule does not lie. If you try to run them 110k, you will be clearing check engine codes every few weeks. The front ones fail first, but I replace them all at the same time and I keep a couple of old rears in case I am short on cash the next time around and need to just replace the front ones with my spare used ones to delay buying four new ones for a year or so (which happened last time).

On these cars, a "Catalyst below efficiency" code usually means that the O2 sensor is getting old and slow to respond. If your O2 sensors are near the end of their useful life, I would replace them before even looking at anything else.

The Airbag light usually means that someone jambed a seat belt tab into a buckle at an odd angle. Electrical problems with the car can also set phantom codes in the SRS. If there is a BMW club in your town, someone will have a Peake SRS tool and can reset the light in about 10 seconds. I own two Peake engine computer tools (needed a new model for the wife's 330) and one Peake SRS tool. Well worth the investment.

[micinnj]

FOLLOW UP ----I pulled the air filter out and blew it off with compressed air ,took map sensor apart and found tree leaf bits traped in the 2 screens inside the map sensor housing ,I carefully blew out housing reassembled and ,the codes cleared -------------------------------I will change the oxygen sensors----------thanks for the reply