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Flex Fuel mounting on NA Chassis

 
Old 06-25-2018, 11:12 AM
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Default Flex Fuel mounting on NA Chassis

It looks like most people here mount their Flex Fuel sensors near the fuel rail - logic being that ethanol content can change by the time it goes from pump to fuel rail on an returnless system.

I however have an NA which is of course a return style system. I am thinking of mounting the sensor near the fuel pump location as opposed to in the engine bay - is this not a good idea? I haven't seen anyone mount it like that yet, so wondering if I should just go for the way everyone else does it.
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Old 06-25-2018, 11:21 AM
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Mount anywhere between pump and rail, but only on feed side not return
Most people mount in bay for easier wiring and plumbing
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Old 06-25-2018, 12:53 PM
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Really? I always thought it was only on the return side, not the feed. Blockage in the sensor results in a rich condition as opposed to lean.

mine is in the passenger side rear fenderwell area by the fuel filter.
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Old 06-25-2018, 02:37 PM
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when we tuned psyber's car he had it on return and e content readings would drop pretty significantly during a pull. moved to feed and problem solved
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Old 06-25-2018, 06:52 PM
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Your fuel should stabilize by the time your car primes and runs within the first 30 seconds of you have a return system.... Unless you have an alternate tank your hard switching from.

As Vlad said, save yourself headaches and put in on the supply line. On mine it would drop ~20% at full tilt and do all sorts of weird things with map interpolation.
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Old 06-25-2018, 07:43 PM
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Thanks everyone! I'll be mounting in the gas tank area on the supply line.
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Old 06-25-2018, 07:48 PM
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I put mine on the "frame rail" where it turns upwards to the rear of the car.

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