Another fault code - Help

[Mike6]

My 2005 2.5i never seems to be happy unless it is showing fault codes. Hot on the heels of having both post cat oxygen sensors replaced by my local (trusted) garage than I get the orange engine light coming back on. Code reader says it is 2883 DME: Mixture preparation bank 2. We had done a few miles on her today including filling up on petrol. Reset code on my driveway and code didnt reappear immediately. Strangely it was Bank 2 post cat oxygen sensor heater element showing as the previous fault. Can anyone point me in the right direction. Thanks

 

[colb]

Check for vaccum leaks first before throwing parts at it, check all rubber and plastic vaccum pipes and hoses for splits or holes, a smoke test will find any you cant find visually. High fuel trims are the usual codes if you have air leaks. I would have expected to see codes for both banks if you do have an air leak. With a good code reader you should be able to see what the exhaust sensors are performing like. Pre Cat should be ranging up and down their voltage range, the post cat sensors usually look preety static unless they are picking up a problem.
What brand sensors did you have put in?

 

[Mike6]

Thanks for that. I have the creator 310Plus so presumably that will work. I supplied the bosch lambda sensors to the garage as I was going to so the job myself but couldn't reach them. In the end garage had a major job getting the old ones out and had to recut the threads on the exhaust. I am wondering if the new one has somehow loosened .

 

[j3nks79]

If there is air getting in around the sensor or around the exhaust joint. The o2 sensor will detect oxygen and it will throw up an engine light/code.
Same with if the engine is running to lean or rich then the sensor will detect oxygen and throw up an engine light.

 

[Mike6]

So, having reset the 2883 fuel preparation bank2 fault took the car out today for a reasonable run. Dash light stayed off until nearly home when I went over a very bumpy section of road and then it reappeared. This time there are two faults for fuel preparation on banks 1 and 2. Am I correct in thinking this is likely to be a small split on the air intake hose downstream of the MAF or the MAF itself needing a clean. If so I will buy MAF cleaner and a new intake boot.