A vehicle fails emissions for high CO and HC at idle. Fuel trims are negative, O2 sensors show rich condition, and fuel pressure is 18 psi above spec. What is the cause?
Our free L1 practice questions act as a diagnostic tool to give you a clear snapshot of your Automotive Service Excellence Level 1 readiness. Discover which topics are your strengths and, more importantly, which critical topics require your immediate attention.
| Name | Automotive Service Excellence Level 1 |
| Code | L1 |
| Vendor | Skilled Trades |
| Certification | ASE |