1FZ-FE Fuel Economy

[mudgudgeon]

Engine has had complete rebuild 15,000km ago. Fuel consumption was 24L/100km (10MPG) Replaced injectors and fuel consumption is now 38L/100km (6.2MPG) Ignition system is new and fuel system is new.

Trouble shooting 101

When you have a new problem after works been done, go back and recheck everything that's been done.
Be suspicious of everything new

1st in your list is engine rebuild.
24L/100km is too much for a fresh engine.
Even if you make the assumption a fresh engine is gonna be tight and use more fuel until it's run in, I wouldn't expect it to use 30% more than what's typical. And by 1500km, it should be running free and easy.

What was your run in procedure?

Had anyone verified the critical mechanical stuff is correct?
See my list above?

Why new injectors?
Were the originals flow tested? Inspected?
How many km in the original injectors?

I've made inquiry's about having injectors cleaned at 250k km, and feedback from more than one supplier has been not to mess with them. Toyota injectiors rarely need cleaning.


Be specific about what's new in the ignition system and fuel system?

New doesn't always mean good. Aftermarket parts can be problematic. OEM Toyota parts can be no good fresh out of the box (not common, not unheard of)

There's loads of people on this forum w with more knowledge than me
The more detailed info you share, the more likely someone is to be able to help.

 

[Brendon85]

Trouble shooting 101

When you have a new problem after works been done, go back and recheck everything that's been done.
Be suspicious of everything new

1st in your list is engine rebuild.
24L/100km is too much for a fresh engine.
Even if you make the assumption a fresh engine is gonna be tight and use more fuel until it's run in, I wouldn't expect it to use 30% more than what's typical. And by 1500km, it should be running free and easy.

What was your run in procedure?

Had anyone verified the critical mechanical stuff is correct?
See my list above?

Why new injectors?
Were the originals flow tested? Inspected?
How many km in the original injectors?

I've made inquiry's about having injectors cleaned at 250k km, and feedback from more than one supplier has been not to mess with them. Toyota injectiors rarely need cleaning.


Be specific about what's new in the ignition system and fuel system?

New doesn't always mean good. Aftermarket parts can be problematic. OEM Toyota parts can be no good fresh out of the box (not common, not unheard of)

There's loads of people on this forum w with more knowledge than me
The more detailed info you share, the more likely someone is to be able to help.

The car was using 24L/100km before the rebuild and any accessories were added. The bores were well worn out as the mechanics showed me when it was rebuilt.

Ran the engine in using mineral oil and varying speed with breaks inbetween to let the car rest and completely cool down. Oil dropped 5000km later after the rebuild and 10W40 Penrite used. Fuel system cleaner used every service and engine flush also used.

Original injectors were not flow tested and I asked them to be replaced with OEM. I needed the car back on a deadline. Live in Alice Springs and I am currently in Adelaide. Good mechanics are hard to find right? Adelaide has an abundance of choices. Original injectors had 380,000km.

 

[Brendon85]

Trouble shooting 101

When you have a new problem after works been done, go back and recheck everything that's been done.
Be suspicious of everything new

1st in your list is engine rebuild.
24L/100km is too much for a fresh engine.
Even if you make the assumption a fresh engine is gonna be tight and use more fuel until it's run in, I wouldn't expect it to use 30% more than what's typical. And by 1500km, it should be running free and easy.

What was your run in procedure?

Had anyone verified the critical mechanical stuff is correct?
See my list above?

Why new injectors?
Were the originals flow tested? Inspected?
How many km in the original injectors?

I've made inquiry's about having injectors cleaned at 250k km, and feedback from more than one supplier has been not to mess with them. Toyota injectiors rarely need cleaning.


Be specific about what's new in the ignition system and fuel system?

New doesn't always mean good. Aftermarket parts can be problematic. OEM Toyota parts can be no good fresh out of the box (not common, not unheard of)

There's loads of people on this forum w with more knowledge than me
The more detailed info you share, the more likely someone is to be able to help.

Using new NGK spark plugs as what NGK recommends, Goss coil packs (still have the OEM) and Bosch sports leads. The whole ignition system is replaced.

New injectors Icon (INJ-136M) and Denso fuel pumps (OEM fuel pumps).

 

[Brendon85]

There were two faults listed. O2 temp sensor was a high voltage fault. Short term and long term fuel trim is at -100% which from what I had researched is as rich as possible. The scan tool lists no faults after the mechanic went over it and reported no faults.

 

[mudgudgeon]

I think the FSM will give testing parameters for individual sensors.

I think you can have faulty sensors that impact the EFI without them showing on a scan tool.

 

[Brendon85]

I think the FSM will give testing parameters for individual sensors.

I think you can have faulty sensors that impact the EFI without them showing on a scan tool.

Sounds good to me. I am hoping they can sort whatever the issue is. Being I have already purchased the ECU and wideband O2, they can still fit that on and tune it for me. I am hoping it comes back with a good result. So far I have replaced two sensors being the MAP and the O2 temp sensor.

 

[Brendon85]

Car was tuned today however has not been released back to me because it needs to have its cold start finished. Initial dyno run showed 40kw at the wheels. Final is now 75kw at the wheels. No fuel figures yet but I will work that out soon after I get the car back.

 

[Brendon85]

OEM injectors are 250cc the injectors I had installed were 400cc. Clearly they are different from the OEM injectors I requested.

 

[mudgudgeon]

I think those numbers are low.

But given mileage, may be to be expected

 

[Brendon85]

I think those numbers are low.

But given mileage, may be to be expected

I will see how it drives and share the dyno graph if I am given a copy. Pick the car up in roughly 18 hours after a cold start tune. Does anyone know what KW/HP an 80-100 series is getting at the wheels standard?

 

[scottryana]

I will see how it drives and share the dyno graph if I am given a copy. Pick the car up in roughly 18 hours after a cold start tune. Does anyone know what KW/HP an 80-100 series is getting at the wheels standard?

Most that I have seen should be in the 100kw to the wheel range.

 

[mudgudgeon]

New, factory fresh power output figures below, at the flywheel.

At the wheels, you lose 40%-ish for all wheel drive

 

[Brendon85]

Before and after on the dyno. Claim from the tuner is they do not make much power at the wheels without forced induction.

 

[scottryana]

That is less than normal, I have dyno'd at least 6 1FZFE cruisers and seen countless others on the dyno they are always between 125-140awhp, 93-105kw. I guess this dyno could be a super heart breaker but it seems like something is off. How does it drive? How does it compare to before the new computer?

 

[Brendon85]

That is less than normal, I have dyno'd at least 6 1FZFE cruisers and seen countless others on the dyno they are always between 125-140awhp, 93-105kw. I guess this dyno could be a super heart breaker but it seems like something is off. How does it drive? How does it compare to before the new computer?

Car drives smoother than before. Might be something in the driveline?

 

[Brendon85]

Car drives smoother than before. Might be something in the driveline?

Or the tuner has gone super conservative.

 

[Brendon85]

Turns out there is a 15-18% discrepancy between some dynos. That coupled with a 40% drivetrain loss near accounts for the results. The landcruiser does drive better since the tune. The tuner also forgot to turn my AC on in the middle of summer. Will be returning tomorrow to get that switched back on.

 

[Brendon85]

Turns out there is a 15-18% discrepancy between some dynos. That coupled with a 40% drivetrain loss near accounts for the results. The landcruiser does drive better since the tune. The tuner also forgot to turn my AC on in the middle of summer. Will be returning tomorrow to get that switched back on.

Fuel consumption is exactly the same. 24L/100km post installing and tuning the ECU with wideband O2.