Probably a stupid question (sry if this is the wrong board) but I got this truck from my dad, it's a 1997 5.2L RWD with about 178k miles. It's been his daily driver since he bought it new and I've been driving it for about a year and it's never revved over 2500ish rpms is this normal for these trucks? Seems incredibly low, I don't drive with O/D off but shouldn't that only affect the revs after 4th gear? I read on a few threads that this could be because of a clogged cat and I hear a rattle after cold starting it sometimes which I've heard could mean its clogged, is there any other way I can check it?

 

You can disconnect the exhaust at the back of the exhaust manifolds and see if it makes any difference. Do you have any codes? You could also check the fuel pressure(should be 49psi).

https://www.allpar.com/threads/the-1...ost-1085223107

 

I have code 31... which is "bad evaporator purge solenoid circuit or driver" is that related? I also had 12 but the guide said not to worry about it.

 

Evap isn't going to have anything to do with it. I am guessing a plugged cat converter. You can remove the front O2 sensor from the exhaust, and see if it drives any better.

 

Just to make sure, the o2 sensor is the cylinder coming out of the cat in-between the two inlet pipes right?

 

Yep, that'd be the one.