p0174 ... bad o2 sensor??

[drobs5]

So my CEL popped on a few days ago in my 97 mk8 so i ran by autozone and had them check the code. The scanner showed p0174 so I came home to search what other people's experience has been with this code. I see a lot of things talking about a vacuum leak, fuel pump going bad, dirty maf, etc but wouldn't all those items cause the car to throw both p0171 and p0174 codes? Since to code is isolated to one side, it makes me think it must be the driver side O2 sensor. Does this make sense? My car seems to be running fine regardless of the CEL but it has always seemed slower than it should be to me.

 

[Roadboss]

How many miles on the car?

 

[MarkVIIIS]

Is there a code for the imrc's

 

[Green Machine]

save yourself some $$ by assuming its a vacuum leak or a dirty MAF. check for a cracked line or bad rubber hoses first. its the cheapest place to start.

get some brakleen and spray around the injectors, intake gasket, and vacuum hoses to check for vacuum leak first. PO174 means bank 2 lean condition. That's a drivers side 02 sensor. its a bitch to get on, but its doable. you do NOT need to drop exhaust.

go with Motorcraft 02 sensors. they work best and fit is perfect.

 

[Hemihed426]

Clean the MAF, change air filter if its dirty, check for vacuum leaks, especially the one on the rear passenger side of intake, if that don't fix it change the O2's. I'd rather pull a tooth from a grizzly bear but its doable...

 

[drobs5]

I will clean the maf and check for vacuum leaks but both of those would cause a code on both banks, not just one, unless the intake manifold gasket is leaking, would they not?

 

[opalescent 96]

If the maf sensor is dirty it will run leaner in general. It's possible to have vacuum leaks affect one bank only. I agree with hemihead426.. should check the easy stuff first. The front 02's are a bitch