Q: I am working on my father in-law's 1999 Ford Ranger. Something caught the wires that go to the Flex Fuel sensor and ripped them out. The truck is not running very well now and is giving the Flex Fuel sensor code. There are a black, a green, and a blue/red striped wire, and I do not know and cannot find any info on how to reconnect the wires. If you can help, it would be great!
A: The Flex Fuel sensor is located near the fuel tank in series with the fuel pressure line routed to the engine (fuel injectors). The sensor detects the amount of alcohol (ethanol) in the gasoline mix, so the Powertrain Control Module can adjust fuel delivery and timing accordingly. Your Ranger's FF sensor circuit uses three wires. According to the ALLDATA schematic, the light blue wire with the orange stripe is 12 volts from 15-amp fuse #13. The black wire is ground, and dark green/light green is the signal circuit to the PCM. If the sensor connector is still intact, with enough wire remaining at the terminals, simply splice the wires together matching colors, while adding more same-gauge wire as needed. Using butt connectors with heat-shrink insulation will do the job.
If the connector is gone, the procedure gets more involved. Contact Ford Parts and ask if it sells the connector separate from a complete harness. If you're lucky, Ford does produce the connector with pigtails, meaning assembled with terminals and lengths of wire that can be spliced/connected to the remaining harness wiring. If it doesn't sell the pigtail connector, but does sell the bare connector, you'll also need the correct terminals and insulators, which must be properly crimped and installed in the connector. The one problem I see with the ALLDATA information is it does not provide a connector view for the FF sensor. The connector view tells us which terminal cavities the specific wires belong in. You should be able to get that additional information from Ford while checking on the parts. No guesswork on this one. One more alternative is finding a salvage yard with a similar vehicle that can supply you with a used version of the pigtail connector.
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