I have a 2000 Grand Am GT (3.4 V6) that has been throwing the code for a small EVAP leak. A gas cap exchange and a code clearing was done, and several days later the code returned. My husband likes to do the work on my car, but he’s not sure where to go with how to diagnose where this leak is. We found that there is a test port for the EVAP system, but is a smoke test something that a DIYer can do himself? And, if so, how? Also, the car has been bucking/hesitating when lugging the engine (low rpms)…could this be related to the EVAP leak? Any thoughts or suggestions are greatly appreciated!
The evap test port was designed to help find leaks fast. Just plug a smoke generator into the port, and look for smoke leaking out. You can check to see if a parts store, like Autozone, may have one on their loan-a-tool program, but you may be stuck with this one. The car is 8 years old. Look around all the vacuum lines for cracked or broken lines, especially the hard plastic lines. It may help to replace any vacuum lines that look cracked or degraded. Unplug and plug back in some of the lines to see if they are loose. You may find the culprit that way.
The bucking andc hesitating could easily be caused by this leak. But, you shouldn’t lug the engine. That causes damage.