ok so im coming up with 111,172,and 173 is this correct and also what these codes mean
little more info would probly help sorry its a 94 flairside with a 5.8 auto 4x4 hope some one can help

 

ok so i replaced the tps and that didnt work i also removed and cleaned the iac and that didnt work im still getting a hesitation or i guess its more the truck is bogging down when i try to take off and it only does it until i floor it then it comes out of it . got the same codes after the new tps could this be a fuel pressure issue ?

 

nobody ? really ?

 

Wish I could help ya.... Did you do a search on the forum to see if anyone else has had the same codes?

 

172= oxygen sensor indicates system always lean
173= oxygen sensor indicates system always rich

I'd say some kind of fuel problem. Or a bad oxygen sensor but could be as simple as a fuel filter.

 

ok so would a bad o2 sesor cause a just a bad reading causing the cel to come on or would it also because of that bad reading cause the system to not deliver the proper amount of fuel ? not really sure how they work lol also which o2 sensor are we talkin about im sure there is several ? thanks for your help sean !

 

I find it odd that you are getting lean and rich at the same time. I would definitely change the fuel filter if you haven't recently and check the fuel pressure. If the oxygen sensor is very old then it wouldn't hurt to change it too and eliminate it as the problem. According to Ymeski they switch slower as they get older. You only have one oxygen sensor.

 

ok thanks ! the po said he replaced the fuel pump and filter within the past year . i tend to believe him since he cut a hole in the bed ! what should my fuel pressure be ? also it tends to do it more when the engine is hot .