FJ Cruisers of Northern California
I got my FJ from a private party on craigslist. The previous owner did some modifications, one of which was a unichip power module. Ive read up on them and they advertise that they 'optimize performance gains from CAIs and cat-back exhausts'. I don't have much frame of reference, but I feel as though I'm getting very poor fuel mileage. I never expected anything more than the stock advertised 19 on the highway, but it sure feels less than that. I haven't done any official measurements or calculations. My question is, could I be getting worse mileage with the unichip in the wrong setting? Should I unplug it if I'm not running any other engine mods?
I hope Nestor will chime in on this, he is well versed in all things FJ including accessories.
The best mileage I ever got from my 2012 was 19.8mpg on a trip to the Bay Area at 65mph.
I certainly did not buy the FJ for mileage qualities, but I can tell you that mpg figures head
south fast if you are not careful with that right foot.
What other mods do you have ? I didnt have unichip but I had heavy armor, 33" MT tires and CAI on my FJ. I think tires and weight makes huge differences. I was getting around 15-16 mpg.
It has an auto trans, a k&n filter in the stock airbox, a 2 1/2 inch spacer lift, A warn winch bumper with no winch and 33 inch rugged terrains.
You will change MPG with the chip. It's made to add fuel when there's more air ( modified intake/exhaust ) but i'm willing to bet the base tune is also altered.
You will get better MPG with the chip disabled/removed. Considering your mods it will be less than stock. Some fresh plugs, and a MAF sensor cleaning couldn't hurt either.
Duly noted, thank you
Worth mentioning the best mod I did which helped my economy was getting an Ultragauge. You can set it up to show many different details but most importantly in this case your calculated MPG current and average. You can easily see when you're being a bit aggressive on the pedal and need to dial it back a bit. It's also fun to hypermile and see how high far you can push it. You would be surprised how just having that number there in plain view will effect your miles per refill.
I'd take that thing off immediately.
Toyota spent tons of time and money mapping the air/fuel/load/throttle position/everything else into the ECU. If there was more power or economy to be had, they would have done so.
The FJ ain't a '73 Monte Carlo.