1998 Honda Civic Error Code P0172

1998 HONDA CIVIC
66,000 MILES • 4 CYL • FWD • AUTOMATIC
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WIATROWSKI
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My Civic has had poor gas mileage (27 mpg) since about 800 miles. I am now getting an error code P0172 - System too rich (Bank 1). What do I look for with this eror code?
Mar 13, 2009 at 11:51 AM
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KHLOW2008
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Hi wiatrowski,

For DTC P0172 the following are possible causes :

Fuel pressure regulator clogged or stuck closed.
Clogged fuel return line.
A leaking fuel injector.
Fuel octane level less than specification.
A deteriorated primary HO2S-1.
Insufficient EGR system flow (D16Y5 engine).
A leaking or stuck open EVAP purge control solenoid valve.
Proper valve adjustment.
Mar 16, 2009 at 2:15 PM