Ford P1090 OBD-II Trouble Code Definition: P1090 Pre-Catalyst Fuel Trim Too Lean Bank 1 P1090 Ford OBD-II Trouble CodeDescription: Causes – Low fuel pressure– Large vacuum leak on engine– Faulty Mass Air Flow (MAF) sensor– Faulty Ignition– Faulty fuel injector Symptoms – Engine Light ON (or Service Engine Soon Warning Light) […]