Check the car
We decode your VIN against NHTSA’s database and run the same checks a mechanic would: injection type, fuel-system age, pump headroom, closed-loop capability. Some cars are a straightforward bolt-on, some need a shop, and a few should not be converted at all — you get told which before you spend anything.
Check the maths
We pull EPA’s measured E85 economy rating for your exact vehicle where one exists, then compare it against pump prices where you live. E85 has to be cheaper by more than the economy penalty, which is a bar most of the country does not clear. If it doesn’t pay, we say so.
A mechanic comes to you
Certified, matched to your job’s difficulty, at your address. Sensor into the low-pressure fuel line, harness to the injectors, controller in the bay, new filter. No workshop booking, no courtesy car, no day off work.
Commissioned, not guessed
They verify the sensor on a multimeter before cranking, watch fuel trims settle, and road-test under load. You get the ethanol reading and the kit’s EPA paperwork — the documents that make the conversion legal, not just working.
After the conversion
Your car still runs on ordinary gasoline.
The mechanism
It measures, it doesn’t assume
The sensor sits in the low-pressure fuel line and reports ethanol content as a frequency between 50 and 150 Hz. The controller reads that continuously and trims injector pulse width to match, so the fuelling follows whatever is actually in the tank rather than whatever you told it at install.
Why it has to work that way
“E85” is already a range
The ASTM spec puts it anywhere between 51% and 83% ethanol depending on the season and the state — winter blends cut ethanol to help cold starts. A kit that couldn’t cope with a moving target couldn’t run E85 at all, so coping with a tank of plain gasoline is the same capability, not an extra one.
What stays put
The factory fuel system
The kit is a sensor in the fuel line, a harness between the ECU and the injectors, a ground, and a control unit in the bay. Your original injectors, pump and ECU stay where they are and keep doing their jobs — which is also why the install is an hour rather than a day.
Practically: fill up wherever you are. If your nearest E85 pump is a forty-minute round trip, run gasoline until you pass one. The only thing you lose by not using E85 is the saving you were checking for in the first place.
The part nobody advertises
Legally, we can fit far fewer cars than can technically run it.
Your car is probably not on it
The check tells you before you spend anything, and it will not let you book a visit we cannot legally perform. A car can be a perfect technical candidate and still have no approved kit — those are two different questions and we answer both.
California is a no today
CARB runs its own approval process and an EPA listing does not substitute for it. We read CARB’s certified-retrofit list in full: it holds electric, CNG, LPG and LNG systems, and not one ethanol system. CARB’s own explanation is that its rules permit E85 kits — almost nobody has applied.
Why we publish this
Plenty of kits are sold to owners of cars they are not approved for. The liability for that lands on the owner and the installer, not the seller — which is precisely why we would rather lose the sale.
Start with the car.
The check is free and takes thirty seconds. If your car shouldn’t be converted, it will say so.