code 172

[95mustang_gt]

172-HEGO(HO2S) sensor fault/lean(right side)

what sould i do first ,change my o2 sensor or check fuel pressure.The car runs fine in wot ,but it does run bad sometimes when at partial throttle.

 

[94-302-vert]

have you cleaned your MAF recently? What about running a fuel system cleaner through the car?

 

[95mustang_gt]

maf i cleaned already,that took my ping away.Fuel cleaner havent done yet.What would you suggest?

 

[mo_dingo]

If your car runs fine at WOT, and bad at part throttle, I would guess that the O2 needs to be replaced.

Usually when you get a single code for the O2's, it's telling you that the o2's are detecting a lean mixture and you aren't getting enough fuel on that side.

But since the car runs fine at WOT, it would make sense that the o2 "thinks" it's lean when it isn't, and is trying to richen that bank too much.

You could still be running lean on that bank, and have an injector problem.
Scott

 

[94-302-vert]

I would say to run one of the better fuel system cleaners, not an injector cleaner. these can be boughr for typically betweeen $5 and $20. I typically go with the $5-$8 stuff.

I would then run this through then clear the codes and see if it returns. if it does I agree that you probably need an o2. Now if you are as cheap as I am you can always try switching the o2's from one side to the other (switch the wiring too obviously) and see if your code follows the suspect O2.

 

[godstangit]

.....

Now if you are as cheap as I am you can always try switching the o2's from one side to the other (switch the wiring too obviously) and see if your code follows the suspect O2.

That is a good idea, I had the o2 come loose creating a leak, tightened it up and cleared the code and all was good