i recently filled up my tank, in a 1997 Verada KF-Xi with normal unleaded and its now sitting at two-thirds full.

from the current tank ive gotted 126.7k's

and all this driving has been in local roads that have been rather quite.


could there be an issue with the engine itself thats making my fuel-eco so terrible?
and is there any ways i can improve it?

Hard to tell, you need repeatable bad fuel results to start looking suspect.
rough engine running? slightly down on power?

if your consistenly getting poor km's from your fuel it's probably something to look into.... I'd say wait until you've burnt through the tank... anything 400+ is probably considered normal
I average 10.4 l/100, but fairly mixed driving.
Anything over 400 I'd be happy with in the TW

That said my VR4 is lucky to get 300kms :) but that's understandable

i recently filled up my tank, in a 1997 Verada KF-Xi with normal unleaded and its now sitting at two-thirds full.

from the current tank ive gotted 126.7k's

and all this driving has been in local roads that have been rather quite.


could there be an issue with the engine itself thats making my fuel-eco so terrible?
and is there any ways i can improve it?

from what i've read, fixes include:

O2 sensor
new spark plugs

KF XI is a heavier car than a magna and will use abit more fuel for that reason. My GF owns a KF EI magna it used a fair bit of fuel compared to my magnas i put a sports exhuast on it and noticed fuel econemy was a fair bit better plus performance was up. Im getting a TJ ecu to get tunned for better fuel econemy.

from what i've read, fixes include:

O2 sensor
new spark plugs

whats the cost of a new o2 sensor?


KF XI is a heavier car than a magna and will use abit more fuel for that reason. My GF owns a KF EI magna it used a fair bit of fuel compared to my magnas i put a sports exhuast on it and noticed fuel econemy was a fair bit better plus performance was up. Im getting a TJ ecu to get tunned for better fuel econemy.

is that using a cat-back system or the whole way?

whats the cost of a new o2 sensor?



is that using a cat-back system or the whole way?

the muffler on these cars are really restrictive. its known if u put a straight through muffler itslef u gain from 5-8 kw power, much better exhaust noise, and better fuel economy
lukey lr2779

The O2 sensor is just before the cat convertor, under the car. Plugs in under the center console. Easy job to replace.

Cost can be as low as $80 and up to $115 depending where you buy from and whether or not you buy a "direct fit" type.

But, put your wallet down. Try a few simple things first - Tyre pressure, clean MAF and throttle body, clean and check battery terminals, service the car ( engine and tranny), check/replace the air filter, look for any obvious obstructions in you inlet starting from the snorkel and working your way back. Check you don't a boot full of dead bodies or twenty bags of cement ei; clean the car out. More weight = poorer fuel economy.

I have a cat back sports system in my car. Great fuel economy. But, I just replaced my cat, which as it turns out was EMPTY! Explains the smell. Fuel economy now isn't so great, but still better than standard.

If you have a multimeter, it is very easy to check whether the O2 sensor is open circuit.
As you have a 1997 car I expect that your sensor is gone. They are supposed to last only 100,000 to 160,000 kilometres.

Some symptoms of a failed sensor are :-
High fuel consumption.
When you are in Drive with a warm engine, does the car want to pull away?
Massive low rev flatspot, then as you accelerate the power really comes in very suddenly..

Gently remove the carpet on the passenger side of the car under the side of the centre console.
There are 2 metal support plates. Remove the 3 screws that hold the front plate in.
Where this plate is closest to the floor of the car is where the sensor plug is.
White flat 4-way plug wrapped in dark gray foam.
2 white leads, these are the heater leads, and a black and a grey lead. These are the signal and earth leads.

I changed my O2 sensor at the weekend, different car after.
Smooth idle
Consumption has improved over 2/100.
The massive flatspot has gone.

Costs- you can get a Bosch universal replacement for around $70. Fitting means that you have to cut the existing wiring and use a set of screw together joiners.
I did my car in under an hour.
Alternatively, MitsFix charge around $130 plus postage for the genuine article.

Most difficult bit will be to remove the old sensor from the front pipe. You will need a good, big adjustable spanner and a bit of strength. Sometimes it is necessary to remove the front pipe from the car to get decent access so you can undo the sensor.

Tricky little grommet and white plastic retainer for the rubber grommet. The sensor wiring from the connector goes between 2 sheets of metal as part of the transmission tunnel. There is a white nylon retainer that has to be unclipped from inside the car so the big rubber grommet can be removed form the uderside of the car.

Summary - I reckon that nearly every car that is over 8 years old has a blown sensor. Treat it like the cam belt and change it at around 120,000Kms and you will be very happy. Mal, would you comment please.

Hope that this helps.
Gerry.

Pretty much agree with Spud

The O2 sensor while may not be open circuit may still be acting "Lazy" which is often the case

There are many things that can cause fuel usage, from what the OP states I think the O2 sensor may be just one of many htings, things like leaky injectors, plugs, leads, dist cap and button are also good places to check

Mal,
Thanks for the comment. I put up with my car "not being right" for several months until I had time to check the O2 sensor. In my case it was open circuit so it was a no-brainer to get another.
Peeps don't forget this is really a service item like a timing belt, Imagine sitting in a hot exhaust gas flow for 100,000 kms plus. That is why people like Bosch or NTK recommend check and replacement.
Gerry

My mechanic claims that the engine light goes on with a failed O2 sensor.

Any credence to this statement?

My mechanic claims that the engine light goes on with a failed O2 sensor.

Any credence to this statement?

It can. But most times it wont my didnt and my 02 sensor was stuffed.

Mine was definitely open circuit on the sensor pair of wires. No indication on the Check engine light.
Gerry