I did some research on these codes
P0141
P0440

I read about o2 sensors, but is there one that seems to set this code off?

Also any thoughts on the P0440 that seems like a standard issue??
Thanks, look fwd to reading!

 

P0440 is a hard one to diagnose.

There are so many damn small reasons it can light up. Could be as simple as a gas cap, could be as crappy as a very tiny hole in a hose for the fuel system vent lol.

I usually recommend trying the gas cap, and if that doesn't work getting the system smoke tested

 

My P0141 code was a shorted out 02 sensor, even though it was a brand new A/C Delco. How many miles on your car? Does it have the original cat converter?

 

167,000+ miles, not too sure about the CAT, I"m going to guess no.

 

When I first bought my '01 Monte SS I had several issues one of which was a P0440 code.

I'm certain mine was the line coming out of the throttle body, and the hose/line that goes from one side of that to the fuel pressure regulator and the hose/line that goes from the other side of that molded rubber connection to the EVAP canister purge solenoid valve. It was completely missing and there was electrical tape over the throttle body.

Here is my thread with the part number for that piece:

https://montecarloforum.com/forum/en...d-hoses-43302/

I'm not saying with 100% certainty that is your problem but I know for sure that it was mine and did indeed throw a P0440. I bought that piece for $30 at a dealer (mistake btw) but could have gotten it for about half that on GM Parts Direct.

Do you have trouble pumping gas? I had trouble and the pump would keep shutting off I was only able to pump about 3-5 seconds of gas and the damn thing would shut off.

 

Everything runs great, that's why I don't get it. I may just reset the CEL and if it pops back on, get it reread and see what shows up.

 

It doesn't look like there is a whole lot that can cause that:

In fact one of the "solutions" is to remove the gas cap and reinstall it and clear the code and drive for a day to see if it comes back. That might actually fix it.

Good luck with it.

 

I notice rust around the outer filler, right near the gas cap seats in there. Any suggestions with that, aside from replacing that whole thing?