1999 Blazer LS (3 button 4x4) 4 Door

I know this DTC = Small Leak Detected but what I would like to know is what is the actual sensor that trips this code and where is it located.

The sensor I would assume is located somewhere in the evap system.
I also assume the sensor measure pressure/vacuum drop?

I changed my gas cap and that didnt fix it.
I might have banged one of the lines that go into the canister in the passenger rear quarter panel when i was installing a class 3 hitch the other day.

I dont have a smoker to fill the lines to find exact location of leak so I was thinking about taping the lines or putting somethihng over the lines like a plastic garbage bag and then taping it up or something like that.

 

its kinda hard to figure out evap codes. alot of the times you actually have to hook a computer to it, manually close the vent valve then smoke the system to find the leak other wise it just comes out the vent valve. for as many times as ive messed with evap codes maybe one out ten times you could actually see the leak, you can check your filler neck where the gas cap presses against, if thats all rotted it will throw it.

double check those lines you think you hit and make sure one didnt crack.

 

what sensor makes the computer give off p0442 and where is it located?

its not a sensor in the EGR system right?
its not a sensor in the fuel supply system right?

so there has to be a sensor in the evap system which is completely seperate from those other systems because if there was a leak in either of those systems they would trip a different DTC code for small leak

 

that i do not know sorry, never really thought about it or had to replace or look for it before

 

this might help you

P0442 - Evaporative Emission Control System Leak Detected (small leak)