Hi..P0171 P0174 codes

This is a very informative forum reason just joined ..2 months ago purch a 2003 325i Bmw...after first 90 miles check engine came on...read at Advance store, P0171 P0174 codes...Oxigen sensors changed...codes erased..after 90 miles codes came again. any suggestions what to check next?? MAF, air leaks..need to know what to look for since Ima DIY guy

thanks
sdcolon

There are several good threads on these codes that I used to diagnose a similar condition on my 2002 Z3. In short, I cleaned the MAF sensor, cleaned the K&N Air Filter, replace the inlet boot assembly (which was badly cracked) and then I reset the codes. After three drive cycles all all on-board diagnostic tests were complete and there were no new pending codes. Parts and cleaner kits were less than $80 US. After the repair the idle speed was slightly lower and the gas mileage was a little better.

Hugh47

HI,

Thanks for the info. will do a quick check around the hoses and vacuum areas to see if there are any leaks...Service Engine keeps coming back after 90 to 100 miles....BMW is running fine and Gas mileage its ok

I had same codes on my 2004 330ci The problem is a air leak after the maf in my case the disa was leaking vacuum at the diaphram

HI...By any chance anybody has photos of those items mentioned, MAF sensor, Air Filter, inlet boot assembly .Im a DIY guy but need some guidance...where is the MAF? Those codes are not an easy fix..they now come back after after 30-40 miles. P0174 / P0171..

Originally Posted by sdcolon

HI...By any chance anybody has photos of those items mentioned, MAF sensor, Air Filter, inlet boot assembly .Im a DIY guy but need some guidance...where is the MAF? Those codes are not an easy fix..they now come back after after 30-40 miles. P0174 / P0171..

You`re in the right Church, but the wrong pew....you need to sign onto the E46 Forum, which is where you should be posting your questions. Great bunch of DIYers over there.