cpierr03

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.

18psi

iTrader: (76)

Mount anywhere between pump and rail, but only on feed side not return
Most people mount in bay for easier wiring and plumbing

Ted75zcar

iTrader: (2)

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.

18psi

iTrader: (76)

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

psyber_0ptix

iTrader: (4)

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.

cpierr03

Thanks everyone! I'll be mounting in the gas tank area on the supply line.

Erat

iTrader: (5)

I put mine on the "frame rail" where it turns upwards to the rear of the car.