Tool Q&A: What to do with troublesome Toyota EVAP codes

Q: If there is a leak in the system, how does the tech perform a leak check? What leak tests do you begin with?

A: The presence of a leak code does not always mean there is absolutely a system leak, according to Heist at STAR Envirotech. For this reason, diagnostic smoke vapor machines for EVAP system testing are often equipped with a high-quality flow meter.

This component is there as an aid in diagnosing the presence of leakage before moving on to the next step of locating revealed leakage with the aid of visible vapor. For the systems in the model years listed above, to determine the presence of a leak: