105 series 4.5 running rich

iow_bob

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Hello I have a 1999 landcruiser 105 series with the 4.5 straight six from an 80 series in it .. Came from factory like this

It has always smelt like it's running rich
Now with it being a 105 it had no cat convertors on it and has no lambda sensors

Running rich was confirmed this month.

It has twin tank's on it and it has emptied both tank's so approx 160 litres in 330 miles .. I've worked it out and it's done 9 mpg

I live on the Isle of Wight so it's almost all round town
But 9 mpg can not be right

Now the other thing is I took it for mot today and it passed . But only just .
Because it's not a uk car it has a non cat test .
Max co2 is 3.5%
And mine was 3.4% on idle
And 998 ppm hydrocarbon

When it was revved up it went to 5%+

So what do I change what can I adjust . Coz i can't live with 9mpg
 

StarCruiser

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Air filter first. I'll set the cat among the pigeons round here if I say take it out for a short trial so I won't. That's the first place I'd go. Then I'm not familiar with that engine set up, but I would then be looking at MAF sensor if it has one, then coolant temp sensor if there is one, then fuel pressure regulator. Look for any small hoses off, especially to the last item. It also might be worth putting some injector cleaner through it.

These are just generic thoughts as I really don't know that engine.
 

Shayne

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I've been to the Isle of Wight and i can imagine you would struggle to hit 60mph in a truck that size , might it be worth taking a ferry trip to blow out some cobwebs on the motorway ? . I have no idea about your engine either but maybe a K&N high flow air filter might balance things out ?
 

Ryan Thomson

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Hey Bob,

From what I have read to the FZJ105's run in an open loop configuration for their fueling so apparently not much you can do with the fuel mix. But check this thread out, seems to be along the lines of the issue you are experiencing. http://www.exploroz.com/Forum/Topic/31709/Land_Cruiser_105_fuel_issue.aspx

I have the 4.5 80 series and I get 12mpg - 19mpg depending on how I'm driving so you can definitely do better!

Let us know how you get on.
 
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iow_bob

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Right I've ordered an 820 ohm resistor and will put that in place of intake air temp sensor.
See if that leans it out
 

Blown80

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Bob, you say your 4.5 Petrol engine is out of an 80 series or do you mean the same as that era.
Does your 4.5 have a normal distributor or the coil packs?
Cheers
 

iow_bob

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Normal distributor .
I'm led to believe it was an 80 series engine they fitted into the 105. But why they removed the lambdas and cats is beyond me
 

Blown80

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Bob, have you fitted that resistor you ordered in? If so any change?
If you're interested, given the earlier version with dizzy cap, there is an advance adjustment you can make which may assist. I can send you the instructions via email. Contact me at [email protected] and I'll send them to you.
Cheers. Chris
 

Ryan Thomson

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Hey Chris, are those the instructions off of LCOOL?

If you could email them my way that would be much appreciated.

Cheers
Ryan


Sent from my iPhone using Tapatalk
 

Blown80

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Not sure of their origin Ryan. I've had them tucked away for years, can't remember. Can you email me so I can reply with them. Cheers
 

105series

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I had same problem with my 105 series petrol, replace your leads + spark plugs with ngk iridium ones. Gives you higher spark and more power/ better fuel economy. Fixed my rich running smell she running sweet as now getting about 25L per 100kms in city, before i was doing 30 to 35L
 
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