Code 171, 174

[REDRUM]

171 (M) Oxygen sensor not switching - system was at adaptive limits - Single, Right or Rear HO2S - Fuel control

174 (M) Oxygen sensor was slow in switching Single, Right or Rear HO2S - Fuel control


Went to Autozone this morning for a belt and used their code scanner. Came up with the above codes.

its a 1999 with 102,600 miles.
original plugs and wires.

question #1 - suggestions for new plugs and wires?


question #2 - will that fix it or does this mean an O2 sensor is bad, which one?


Thanks guys,
Somebody always knows the right answer on here.

 

[bikerboy]

Try cleaning the MAF sensor with a good electrical cleaner and let it dry. The disconnect your battery to reset the PCM. Go Drive it and see if it drives better, do a few hard throttle accelerations.

 

[REDRUM]

it's not running bad. there has been no difference in how it runs since the light went on.

 

[wahlstrom1]

Very good chance there's a vacuum leak. It's usually between the lower intake and the fuel rail, it's common enough that ford actually made an improved version of the gasket to solve the issue. I had to use Ether to make it show up, propane and WD40 didn't do it...

-andrew