Why am I getting 11.5mpg?

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Joined
May 29, 2014
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23
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307
Location
Scottsdale
Someone please chime in, I’m baffled. I’m getting 11.5mpg with my 1FZ-F engine and my exhaust smells a bit rich. Any ideas? The choke is open once things warm up.
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Thats great! Its a landcruiser! Check your O2 sensors if running rich
 
Hello,

What is your idle speed?

Check the vacuum lines for leaks.





Juan
 
Carb was inspected in Dubai before importing.

Where is the idle mixture screw? I’m not finding any info in my maintenance manual or online.

Idle speed is 750ish

I’ll check for leaks
 
Carb was inspected in Dubai before importing.

Where is the idle mixture screw? I’m not finding any info in my maintenance manual or online.

Idle speed is 750ish

I’ll check for leaks

Hello,

Idle speed is within range.

The idle mixture screw is on the block side of the carburetor, below the accelerator cable. GCC spec trucks require an SST to adjust it, though.

The idle adjustment procedure is in the Engine Mechanical section of the 1FZ-F FSM. Carburetor adjustment is in the Fuel System section.

Take the chance to clean the distributor. If possible, replace the sparplug cables.







Juan
 
@javelinadave, Along with what others have said, what do your plugs look like? I have a setup identical to yours and would guess my fuel economy is in that ballpark for mixed city and highway driving. I pulled my plugs and they all looked fine and showed an appropriate mixture but they were worn. I ended up replacing the plugs, spark plug wires, distributor cap and rotor. Engine definitely runs smoother now and will run a mpg calculation in the coming weeks. I'm also going to check the valve clearance so I have a comprehensive baseline.
 
Someone please chime in, I’m baffled. I’m getting 11.5mpg with my 1FZ-F engine and my exhaust smells a bit rich. Any ideas? The choke is open once things warm up.
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It not a Prius 😎

Sorry in advance, I couldn’t help myself !

Really thought you didn’t buy a LC if you’re concerned about MPG
It’s all about Smiles Per Gallon 😉
 
Plugs, wires, cap and rotor are new, I need to check the rest. If 11.5mpg is normal than I just need to figure out the running rich smell.
 
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Plugs and wires are new, need to check the rest. If 11.5mpg is normal than I just need to figure out the running rich smell.
I'm guessing it doesn't have catalytic converters - correct? We're pretty spoiled by modern vehicles with very cleaning burning engines and cats. The exhaust is basically odorless when the vehicle is warmed up. Not so with older carb'd, cat-less vehicles - they almost always have a very strong exhaust smell.
 
Plugs and wires are new, need to check the rest. If 11.5mpg is normal than I just need to figure out the running rich smell.
so, how much have you driven it since you've had it? i'm asking because i want to know if you have a baseline and your noticing this mpg and exhaust smell as new?

11.5 can be a bit low depending on conditions and right foot, but still anything over say 13mpg combined average real world driving is going to be pretty good. and the exhaust smell that seems rich to you could be rich or, like me, takes me back to a simpler less complicated time in my life thats not only normal but enjoyable.

aside from anything needing actual repair or replacement a propper tune-up is all you can really do, and its all the rig will ever really need. i think you have electronic ignition but if you do have points, a proper tune-up includes a gap/dwell check and a flaot height check.
 
Plugs and wires are new, need to check the rest. If 11.5mpg is normal than I just need to figure out the running rich smell.

Hello,

I forgot to mention that in a 70 Series you can get up to 13 mpg or 21 km/gal from a 1FZ-F engine on city traffic, provided that the carburetor is well tuned, the fuel system is in good working order and you keep your right foot light. Highway mileage can go up to 17 mpg or 28 km/gal. Hint: the 1FZ engine runs happy (and fuel-efficient) between 2000 and 2400 rpm.

If the engine idles smoothly, the rich smell is due to the mixture. Again, the adjustment procedure is in the FSM. Get yourself an adjusting SST before attempting it.

I would adjust the screws a little bit as per the FSM. If I would get 12 to 12.5 mpg after that, I would call it a day and enjoy the ride.






Juan
 
so, how much have you driven it since you've had it? i'm asking because i want to know if you have a baseline and your noticing this mpg and exhaust smell as new?

11.5 can be a bit low depending on conditions and right foot, but still anything over say 13mpg combined average real world driving is going to be pretty good. and the exhaust smell that seems rich to you could be rich or, like me, takes me back to a simpler less complicated time in my life thats not only normal but enjoyable.

aside from anything needing actual repair or replacement a propper tune-up is all you can really do, and its all the rig will ever really need. i think you have electronic ignition but if you do have points, a proper tune-up includes a gap/dwell check and a flaot height check.
Been driving it since September. Milage has been pretty consistent and I drive pretty conservatively. The tail pipe is a bit sooty and I need to pull the plugs next week when I get home from work. I'm also going to change out all the vacuum hoses as a precaution, cheap and easy thing to do.
It is what it is, I didn't expect Prius milage but was a bit surprised at what I'm getting.
Thanks for all the replies! I'm coming over from Land Rover turbodiesels to this.
 
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