← Back to list

2003 Dodge Neon SXT Evaporative Emission System Leak: Symptoms, Codes, and Fixes

Model: 2003 Dodge Neon SXT Fault Code: P2177 Posted: 2011-01-19 13:50

A few weeks ago, my 2003 Dodge Neon SXT began experiencing power loss while driving uphill. The RPM gauge would surge, but the car failed to gain speed—this only occurred on the return trip from shopping; no issues were present during the outbound journey or the first 20 minutes of the drive home. After checking transmission fluid and engine oil (oil was low, so I topped it off), the vehicle ran normally in town until a few days ago. Recently, I noticed a new swishing sound coming from near the front of the car. This noise appears even when the vehicle is idle in the driveway. I tested the car by driving around a circular drive three times without any issues, then parked and let it sit for about 10 minutes—after that, the sound returned. My check engine light has triggered two OBD2 codes: 'Evaporative Emission System Leak (very small)' and 'Evapor-ative Emission Control System Leak (small)'. I'm wondering if these emission-related issues are connected to the power loss or unusual noise. Could this be a fuel system or vacuum leak issue? What should I check first?

Related fault codes
P2177
Comments (2)
Anonymous 2011-03-17 01:03

The swishing sound might indicate a failing power steering pump—check if you're experiencing any steering issues, such as difficulty turning, hard steering, or weak kickbacks during turns. While the evaporative emission system is related to fuel vapors and vacuum pressure, a loose or faulty gas cap gasket could contribute to both the emission codes and minor surging. However, this sound is less likely to be directly caused by the emissions system itself.

Anonymous 2011-03-21 21:10

I recently encountered the same error code on my 2003 Dodge Neon SXT. Possible causes include: - A loose, improperly sealed, or missing fuel cap. - A bent metal flapper under the gas cap that doesn't seal properly—this can allow fuel vapors to escape and disrupt vacuum pressure. - A hole or crack in any of the vacuum hoses connected to the engine or emission system. The OBD2 code indicates a failure to maintain proper vacuum levels. Since this is a sealed, pressurized system, even small leaks can trigger these codes. I recommend visiting your local AutoZone for a free troubleshooting guide and consulting a mechanic to assess potential fixes—especially checking all vacuum lines and the fuel cap seal.