It can be difficult when a customer comes into the shop with a vehicle that is running multiple codes. Pinpointing the issue could feel like trying to find a needle in a haystack. Recently one SureTrack community member ran into this issue when a customer brought in their 2006 Kia Rio LX 1.6 with a check engine light on and 4 trouble codes being read. Here’s what the technician figured out.
Diagnosis
When the technician connected the scan tool, he found these codes: P0171 – System Too Lean (Bank 1); P0446 – Evaporative Emission System Vent Control Circuit; P0507 – Idle Air Control System RPM Higher than Expected and P2187 – System Too Lean at Idle (Bank 1). He monitored live data using the scanner and found that the oxygen sensor (B1-S1) voltage was fixed below 450 mV, indicating a lean condition. When the engine was idle and propane was induced into the intake manifold, he found the oxygen sensor (B1-S1) signal responded to the rich condition.
He then connected a smoke machine to the EVAP system and found smoke leaked from the EVAP vent valve and the system was unable to hold pressure. He removed the EVAP hose from the engine intake manifold, found smoke leaked from the EVAP purge solenoid valve and used the scanner to command the EVAP valve to open and close. Smoke continued to leak, indicating that the EVAP purge solenoid could not close. After applying voltage and ground, the EVAP purge solenoid valve was inoperative. It was clear to the technician that this had to be the issue.
Fix
The technician ended up replacing the EVAP purge solenoid valve which solved the issue. The Kia Rio was returned to a happy owner. Read the Real Fix in the Mitchell 1 ShopConnection Blog.
