Fuel Consumption. 4.2 EFI about 22 L per 100ks

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25th July 2016, 03:42 PM
kbchez

Fuel Consumption. 4.2 EFI about 22 L per 100ks

:SNruQWn369624407:

I know they do drink alot but 22L per 100ks Now to tune the engine more. Taking out the lpg mixer to air intake.
Then check timing. Repair airbox its broken. has anyone got the text readings for the water sensors so I can make sure they are working correctly.

Many Thanks
Kevin:coffeetime:
25th July 2016, 08:42 PM
rods gq

Yes a little high but even all tuned up and if on all terrains will struggle to do better than 17

Sent from my SM-G900I using Tapatalk
25th July 2016, 09:08 PM
kbchez

Thanks mate.

That will be about 5l per 100k's better. thanks
25th July 2016, 09:09 PM
kbchez

What was the nissan saying when they first came out about the fuel consumption.. that would be interesting
25th July 2016, 10:07 PM
dom14

Quote:

Originally Posted by kbchez

:SNruQWn369624407:

I know they do drink alot but 22L per 100ks Now to tune the engine more. Taking out the lpg mixer to air intake.
Then check timing. Repair airbox its broken. has anyone got the text readings for the water sensors so I can make sure they are working correctly.

Many Thanks
Kevin:coffeetime:

For a 4.2(EFI), it looks ok. I haven't seen or heard of many 4.2s with 15L/100km figure.
Heavy car/bigger engine combination is not built for fuel economy.
25th July 2016, 10:53 PM
Bigcol

I used to get about 15L Dom - and as bad as 26L when towing
thats why I had it re-tuned for Gas performance

they are thirsty big buggers,
but
get all the wiring sorted
electronic Ignition
extractors
good tune up

you will be amazed at how good you can get them to run
26th July 2016, 12:05 AM
kbchez

thanks bigcol,
Its already got extractors,
What sort of electronic Ignition, you talking about.
I will be removing the LPG for now. It leaks gas under the bonett and its old as type.
26th July 2016, 09:00 PM
billyj

where are you located mate? it wuold be a good idea to get someone to plug in a scan tool like an ecu talk so you can see exactly what the sensors are reading while running.
you dont need an electronic ignition the tb42e is already computer coltroled for the timing and fueling. its only the carby boys that replace the points in there dissys with an electronic ignition setup
other things to check are the thermostat as if its not getting to proper temp it will run rich

my best econ was 13l per 100kms avg being about 20l. currently getting 20-25l per 100km towing 2 tons daily but my tb42e is turbo charged these days
26th July 2016, 10:28 PM
dom14

Quote:

Originally Posted by billyj

where are you located mate? it wuold be a good idea to get someone to plug in a scan tool like an ecu talk so you can see exactly what the sensors are reading while running.
you dont need an electronic ignition the tb42e is already computer coltroled for the timing and fueling. its only the carby boys that replace the points in there dissys with an electronic ignition setup
other things to check are the thermostat as if its not getting to proper temp it will run rich

my best econ was 13l per 100kms avg being about 20l. currently getting 20-25l per 100km towing 2 tons daily but my tb42e is turbo charged these days

Hey BillyJ,
How did you manage 13L/100km economy on TB42?!
What did you do to get that economy?
Thanx mate
27th July 2016, 12:57 AM
kbchez

thanks all,
I'm in Albany WA.
A scan tool would be great, The first thing I changed was the thermosta. put in a high flow. The old one was not opening properly and it was bent.
That scan tool you are talking about is it a OB2 scantool. The sparkplugs are a white colour. Timing light on order. via ebay.So I cannot do much more till the timing is reset. I do know that if its close the ECU computer should work it out to correct timing. So Im just going to turn the dissy till it sounds better for now.
I have been thinking thats dangerous. These patrols where proberly designed for the US market. so fuel consumtion not a worry. Most likely If these machines where geared down about 500RPM. fuel usage would improve. But what a drama that would be. Is the Auto gear boxes on the petrol the same as the diesel. ??????.....

thats enough for now lol.

Thanks
Kevin
27th July 2016, 04:38 PM
billyj

Quote:

Originally Posted by dom14

Hey BillyJ,
How did you manage 13L/100km economy on TB42?!
What did you do to get that economy?
Thanx mate

no idea how i pulled it off, but on a trip out dargo way it did 13l per 100km on the fwy between werribee and sale
27th July 2016, 04:47 PM
dom14

Quote:

Originally Posted by billyj

no idea how i pulled it off, but on a trip out dargo way it did 13l per 100km on the fwy between werribee and sale

I thought you might have done some clever tweaking of the ignition & fuel system to get that, and probably some diff/tranny/wheel size tweaking as well. Either way, I'm sure it's quite doable, just not sure how to approach it without spending a fortune.
27th July 2016, 04:48 PM
threedogs

Quote:

Originally Posted by kbchez

What was the nissan saying when they first came out about the fuel consumption.. that would be interesting

Just so happens I have an early road report which states the following ::
A SWB auto will return 18.8/100km
LWB manual wagon 14.8/100km
and the trusty 4.2td about 11.3/100
their figures not mine 4x4 aust magazine
27th July 2016, 04:51 PM
dom14

Quote:

Originally Posted by kbchez

thanks all,
I'm in Albany WA.
A scan tool would be great, The first thing I changed was the thermosta. put in a high flow. The old one was not opening properly and it was bent.
That scan tool you are talking about is it a OB2 scantool. The sparkplugs are a white colour. Timing light on order. via ebay.So I cannot do much more till the timing is reset. I do know that if its close the ECU computer should work it out to correct timing. So Im just going to turn the dissy till it sounds better for now.
I have been thinking thats dangerous. These patrols where proberly designed for the US market. so fuel consumtion not a worry. Most likely If these machines where geared down about 500RPM. fuel usage would improve. But what a drama that would be. Is the Auto gear boxes on the petrol the same as the diesel. ??????.....

thats enough for now lol.

Thanks
Kevin

If you follow the part numbers of the auto tranny between petrol & diesel one from the repair manual, that should be able to tell you.
I thought turning the dizzy is a no gone zone for EFIs as the advancing/retarding is done by the ECU once the valve timing is set manually.
27th July 2016, 05:02 PM
billyj

nah nothing clever, just 2" lift 33"s and loaded to the hilt heading bush. i couldnt believe it so i had 3 people check my calculations
28th July 2016, 01:16 AM
Arfa Brayne

Quote:

Originally Posted by billyj

no idea how i pulled it off, but on a trip out dargo way it did 13l per 100km on the fwy between werribee and sale

Sure it wasn't between Hotham and Sale ??............. Downhill with a tailwind and it's ears back ?

My 4.2 efi manual gets 22/100km LPG, the old 4.2 carby auto had no trouble burning 30/100km.
Might have to take the rocks out of me Blunnies.
28th July 2016, 08:35 PM
billyj

yep im sure, only thing that i can say it it was not long after doing the head so everything was fresh, plugs leads, injectors cleaned, new 02 sensor, new temp sensor/sender etc
29th July 2016, 03:46 AM
kbchez

Hey Billyj, I have found the ECU stuff on the net It looks like I just need to purchase the plug and cable , already down loaded the software for it.

Once the cable turns up I supose its going to be a real learning curve for me.
29th July 2016, 05:10 PM
billyj

all the software and cable will allow it to read the sensors in real time, so you will see differnt numbers going up and down etc, it showed i had a blown o2 sensor as its voltage should fluctuate and it was sitting on a steady .3v and never moving fitted a newie and moving between 0-1v like it should
29th July 2016, 05:25 PM
dom14

Quote:

Originally Posted by billyj

nah nothing clever, just 2" lift 33"s and loaded to the hilt heading bush. i couldnt believe it so i had 3 people check my calculations

You must have done something right probably following a bit of gut feeling.
That economy is damn good.
I would like to get good fuel economy from my troll(RB30 LPG), without shortening the lifespan of the motor, of course.
I haven't seen any difference between EFI converted RB30 & properly tuned carby/mixer RB30.
Of course, I'm going by what I've heard so far.
29th July 2016, 05:29 PM
dom14

Quote:

Originally Posted by Arfa Brayne

Sure it wasn't between Hotham and Sale ??............. Downhill with a tailwind and it's ears back ?

My 4.2 efi manual gets 22/100km LPG, the old 4.2 carby auto had no trouble burning 30/100km.
Might have to take the rocks out of me Blunnies.

Yeah, the autos are usually slightly thirstier.

You didn't like the comfort of the auto tranny?!! :)
29th July 2016, 05:31 PM
dom14

Quote:

Originally Posted by billyj

yep im sure, only thing that i can say it it was not long after doing the head so everything was fresh, plugs leads, injectors cleaned, new 02 sensor, new temp sensor/sender etc

That is true. Most of the performance/economy gains can be reached by servicing, cleaning, upgrading the ignition system alone.
29th July 2016, 06:43 PM
kbchez

With the ECU talk does it tell you what the fault codes mean. As to what the fault is. Or do I need a list of the Nissan fault codes.
When you say the O2 sensor, do you oxygen sensor on the exhaust.
One thing I have found over the years with EFI and computers is that the engine temp must be perfect and its temperature sensors working. If not the computer will say engine cold more fuel needed. And I supose if there is to much crap around the senor in the engine the senor will not work correctly either.