3fe fuel problem insane fuel consumption

[ChaseTruck]

So. Disclaimer first: I never had a 3FE; never will.
If you fill up the tank, and it's empty after you drive, there are only so many places the fuel can go.
1. Someone pumped some out of your tank when you weren't looking...
2. Fuel never makes it to the injection system because it is leaking somewhere on the way to the injectors - hole in gas tank, hole in a fuel line, a leaky fitting somewhere.
3. If fuel makes it to injection system, and some of the injectors are grounded, they will just spray fuel, without input from the ECU. So, perhaps a wiring fault in the injector circuits.
4. If fuel is properly metered by ECU & injection system, it needs to be burned in the engine (...and not in the catalytic converter, assuming there is one) to make power. So you need spark.

My armchair quarterback guess is that one or more injector circuits have a ground fault, and what you're smelling is whatever the catalytic converter does with the excess fuel.

And I'd pull an easy-to-reach fuse anytime before I would try to disconnect a multi-pin connector at a difficult-to-reach ECU. But that's just me.

 

[jonheld]

Hello,

The procedure I mentioned is what the FSM recommends.

Manuals and procedures exist for a reason.

It is easier to remove a fuse for a reset but it not the way the designers developed.

ECUs are expensive. I would not risk one by cutting corners.





Juan

Electrically, it makes no difference if you remove the EFI fuse, disconnect either battery terminal, or unplug the ECU. Each one will accomplish the same thing. The ECU doesn't care which one you choose and none of them will cause damage.

By all means, do what you feel is best.

 

[leonard_nemoy]

Definitely check the brakes

 

[GRiP]

Chasing up a similar issue with my 80 3fe. It runs on duel fuel LPG and petrol fuel economy has dropped from 300-400km a tank on both fuels to about 200-250km a tank on both fuels in the last 10 years. I have put on bigger tyres 33inch and 35 inch lift is about 5 inch roof rack with solar panel, awning and spot lights. Changed plugs, leads, dizzy, air and fuel filter desmogged.

 

[Marco Lau]

I avg. 11mpg on 37s 6200 lbs fully loaded with 4 ppl. on my way back from Moab.
air/fuel filter, 02 sensors, spark plugs.....basic stuff first