Cat starting to come apart

[Carder09]

Do the sensors and cats if you want, if your sensors have not been replaced then replace them.

[Dirtautoguy]

So I don't have a temperature gun but I'm looking for one or I might borrow one. I looked at my MAP sensor readings at idle and rev at about 2000 rpm at idle it read about 3.4 rev it read 4.5 I'm not real sure what those readings mean. I have also seen it up around 11 before but I didn't note when

[Carder09]

Those voltages may not be correct, you need to bench test that MAP sensor, that said, you will need a vacuum gauge for the most accurate readings, but with no vacuum, key on, you should get 5v DC, the more vacuum you apply, the further the voltage should drop, 4.7-1.1v DC. Though testing that MAP when there is not check engine light is kind of pointless IMO, get rid of them cats, or replace, and change your sensors and truck on.

[Dirtautoguy]

Just out of curiosity could I be not getting a code on the cat because the o2 sensor isn't working properly? Although I'm getting 18-19mpg on the highway with 3.42 gears is that about right?

 

And I'll look into my map sensor soon.