My service engine light came on a few days ago, I took it to advanced auto and the guy told me the codes were: Bank 1 system too lean and bank 2 system to lean. When I got home I checked the internet and one of the things suggested was to clean my MAF sensor. I went to RPM and asked them how much to clean the sensor. The salesman there told me that the only reason to clean the MAF sensor was if there was a moth stuck in it. He told me I should have it replaced for $215, but that first I should have a diagnostic done for $100. Needless to say I left and looked up how to clean the sensor myself, and then did it! I reset the light and then this afternoon the light came back on. Is there anyway to do a diagnostic on the o2 sensors w/o having to remove them? Everything sounds fine and my gas milage hasn't changed. I don't have a lot of money to invest in this right now, however I don't want this to turn into something that will cost even more if I do nothing.

 

The 02's are working fine, as they are indicating a lean condition. A lot of people misenterpret those codes to a faulty 02, which it is not. It is more than likely a vacuum leak. Most common place would the pcv hoses from the passenger valve cover that run to the back of the throttle body. There is a rubber elbow way in the back that is hard to reach and was prone to cracking, causing a vacuum leak... = lean codes for both banks. It never hurts to clean your maf for any reason. But check for that vacuum leak. Completely remove the line to inspect it. The elbow in the back (hard to reach and not visible) will just pull off but may take some twisting. If you find that it is cracked, I believe it is a dealer part only for around $13. To clarify, were the codes P0171 and P0174? Vacuum leaks will most likely be the cause of the lean condition codes. There are other things to consider but start there.

Btw, that salesman is a fool. Trying to sell you a maf.. wow. They can easily be fouled/dirty and be cleaned with care.

 

I believe he was trying to hustle me. It took me all of 15 minutes to clean and reassemble my MAF. I will check for a vacuum leak in the morning. Thanks!