Failed inspection p0171 & p0174

[dking]

Just went to get my 2000 Explorer 4X4 4 Door XLS inspected and they came back and told me it FAILED. Just what I needed. I have 60 days to correct the problem. Check engine light is on. OBDII codes P0171 and P0174. They want $160 to replace both 02 sensors. Price don't sound to bad since the parts are $57 ($114 total) each at AutoZone. Just seems strange that both would go out at the same time. Is there anything else that could cause these codes? I don't mind doing the work myself just don't want to replace parts and still have the same problem.

 

[jremington59]

I'm not sure what this has to do with the 02 sensors. Other than they detected a lean fuel to air ratio. Here's info I found.


•In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
•Inspect all vacuum and PCV hoses, replace if necessary
•Check for a dirty fuel filter and proper fuel pressure

 

[drdoom]

If its a V6 check the intake gaskets also. Clean the IAC valve too. And as jRemington59 stated, check for vacuum leaks. When I had P0171 & P0174 it was a hose tee knocked loose at the IAC.

 

[dking]

Thanks jremington59 and drdoom I'll check it out all out this weekend if the doesn't rain. Working the graveyard shift the next 2 days. Yes it's a V6 sorry I left that out.

 

[jremington59]

I'd clean the MAF first of all and see what happens.

You also want to buy Mass Air Flow Sensor spray cleaner to clean it. The others they suggest can leave a residue.

 

[dking]

Well I was able to clean the MAF and IAC today after work the CEL is now gone. Thanks for the input. It saved me $160 big ones. Thanks again for everyones help this is why I love this forum.