Fuel economy

[Paul_JJ]

ive got an auto with mild mods and i get around 200m/320km off a tank of fuel with my standard normal driving i do get 250m/400km if its all motorway driving.
bareing in mind i have a MK1 so i only have an O/D switch and PWR or MANU button
i did notice a loss in my mpg when i put in an upreated fuel pump but nothing major.

and yes i am crazy enough to have had mine out on track as well and didnt really cook the brakes up that bad.
(tgtt llandow track day and trax (silverstone GP circuit))
also when i first got my GT before modding i did a 1/4 mile day as well with it.

What was the 1/4 mile time?

 

[Valdas]

Completly standard glanza full tank gets me nearly 500km . Usually get at least 400km depending how i drive it

 

[thomllee1981]

almost stock (no engine mods) in the damp i did a 16.05
dont know what it will do now if i retune the engine again i am hoping around 15
but had to untune her had a few issues but am working back towards a steady 1bar auto.

 

[Paul_JJ]

almost stock (no engine mods) in the damp i did a 16.05
dont know what it will do now if i retune the engine again i am hoping around 15
but had to untune her had a few issues but am working back towards a steady 1bar auto.

What exactly was the problem? I plan to tune mine to 1 bar - and I have an auto! I heard something about the BOV for an AUTO won't do any good? have you got an aftermarket bov?

16.05 is good - is it on 1 bar? what other mods have you got? What would be the time on stock boost?

This week I've managed to get 150 miles per half a tank, and most of the time I was using NORMAL mode, the secret is not to get the car over 3K RPM and don't touch the brakes at all - only touch them if you drive below 10mph and have to stop. Manu is not very good if you got over 40 mph as it doesn't go to overdrive straight away even if you have O/D on all the time!

 

[thomllee1981]

What exactly was the problem? I plan to tune mine to 1 bar - and I have an auto! I heard something about the BOV for an AUTO won't do any good? have you got an aftermarket bov?

16.05 is good - is it on 1 bar? what other mods have you got? What would be the time on stock boost?

This week I've managed to get 150 miles per half a tank, and most of the time I was using NORMAL mode, the secret is not to get the car over 3K RPM and don't touch the brakes at all - only touch them if you drive below 10mph and have to stop. Manu is not very good if you got over 40 mph as it doesn't go to overdrive straight away even if you have O/D on all the time!

mines a MK1 mate i dont have these extra option buttons its only got an overdrive on/off button.
and mine is used mainly around town i dont have to do many long journeys so this affects the fuel economy as its a lot of short trips and stop start trips with all the traffic lights.

16.05 was on stock engine all it had was a set of alloys and D2 coilovers. so pretty stock.

the problem i had with 1bar is i cracked my mani! then i had a few engine issues so down tuned it.
and i got 1bar by using controlled boost creep.
the problem with running uprated boost on the auto is that it doesnt dump on gear shifts so you get big spikes of power on the gear changes.
the best way of controlling it is an external wastegate. as the internal one cant hold it at a constant.
but if you put them boost up dont forget to remove fuel cut and correct your fueling or you will have lots of problems!
the stock BOV is fine at 1bar but no doubt you will relocate the airfilter so or fit a FMIC so you will need to get a new BOV anyway.
mines running a R2D2 off an R32 skyline works perfectly.
if you want to see my cars spec sheet its up in my members garage page mate.

 

[koolgtstarlet]

AT Gearbox Error Codes through O/D Light

Dear Paul,

Noticed in you post you mentioned that the book has the codes for the AT gearbox, can you share this information and how to put the ECU in diagnostic mode to read these codes?

Many thanks,

Andrew

Well the book says:

Both buttons OFF - Economy mode!!!!! Used for normal driving!
PWR - SPORT mode!
MANU (MAN) - Ice and SNOW mode!

Well now on my OWN experience! The manu IS TRULY ice and snow mode - and it's not just save on petrol it improves the traction on ICE ans SNOW, RAIN -)))
PWR mode - is totally useless - complete waste of petrol - as soon as I put this on - I can literally see my petrol gauge going down every time I push the accelerator -) Yes it gets to the red line - same with the "economy mode", better kick down? may be 5% better than the "Economy mode" - hard to notice (on my car) may be you have better experience! One thing for sure it stays for long in gears and doesn't change them very often - maybe good for the track -) but who will take an AUTO on the track? and at the end of the day - if I change them manually 1st,2nd then D - it would be faster and a lot more power than PWR button!

No button pressed is what I would normally use on the motorway and for overtaking!

Used to drive in "Economy mode" now I drive in MANU mode most of the time and does save on petrol pretty much!

According to my book - the low boost was designed to provide better traction in bad weather conditions -) also to be used when driving on the mountains!!! (Japan has a lot of mountains) - the TURBO gets A LOT more oxygen in on the higher altitudes (ever wondered the construction of the plane engines?) - so for some people driving let's say 3K miles above the sea level - it could be a surprise to get an additional Boost, which could lead to the accident - to prevent that the LOW boost was invented!

One more thing!!! It cools down the turbo - so it would be VERY clever after a hard drive - to put the LOW boost ON (if you've ever watched Starlet GT racing in JAPAN - can be found on the YOUtube - the driver puts the low boost ON as soon as the race stops - last seconds on the video!)

To be good for the engine and the box - would be a MANU mode -) as you will have low RPM most of the time, save on petrol and don't stress the engine - even if you go uphill it will automatically drop the gear - so the gearbox won't overheat!

Another thing is - having O/D off - would make your car faster, and put less stress on the gearbox! The book says that you have to be careful and don't use the O/D if you're going UP hill.... that would increase the life of the gearbox - and I would assume the engine as well - low rpm up hill - don't do any good to the engine either!

Forgot to add my dealer which I've bought the car from - SVA Imports - trading for years with JAP import and having most of them an AUTO - didn't know that a MANU mode is for Ice and SNOW he used that as a MANUAL so that would allow to change the gears manually - so when I was test driving my car and changed the gears - he told me that I can't do that and I suppose to use the MANU mode -) On which I explained to him about my book and what is the MANU actually for!

Electronically-Controlled Transmission - does it say - ECT-S on the dashboard??? Electronic Controlled Transmission - SPORT - and don't forget that the actual gearbox is hydraulic, but with sensors (inside the gearbox) and separate ECU to control the gearbox! I even have the gearbox diagnosis codes in my book when the O/D light will flash certain amount of times and give an error code just like an Engine Management Light for the Engine -)

 

[Paul_JJ]

Dear Paul,

Noticed in you post you mentioned that the book has the codes for the AT gearbox, can you share this information and how to put the ECU in diagnostic mode to read these codes?

Many thanks,

Andrew

http://www.toyotagtturbo.com/forums...Diagnosis-codes!-A-Guide!&p=953610#post953610

 

[chrisinflight]

What is the mpg like Chris? I'm going for a record on my this week, this the combined driving and I've got 130 miles already and not even half a tank, about 35% of the tank -) In theory should go to 300 miles per tank -)

I`m just about to hit the reserve light on the dash and the odo reads 230km. Basically I`m still only getting 220 to 250km per tank whichever gearbox mode I`m in. Short journeys with hills mean I do brake quite a bit. esp. in the Manu mode. I`m going to fit the lambda-sensor this afternoon.

 

[Paul_JJ]

That is really bad Chris! I would get the same mileage if I was getting 7K rpm everytime I drive a car!
I've got 180 miles (291 km) per £35 this week - about 27L. = 30 MPG! And that is AN AUTO - not to mention cracked mani and blown mani to turbo gasket! Most of the time I use normal mode and when in city use manu mode!

Did you put the cardboard in front of the radiator? I must admit short journeys on my car are horrible as well - I drive on average 16 miles per journey and around 35 a day!
I'd say there is definitely something wrong with your car if you drive it steady and get such MPG.

 

[koolgtstarlet]

Thank you Paul, from the way the car is acting I suspect it is the No. 1 solenoid - shift. Additionally, I think that driving with Manu - ON, Turbo - LOW gives the best millage. Since, the O2 Sensor - first one at Manifold would see more O2 in the exhaust on HIGH boost and add more fuel to the mix. Thus leading to worst millage. That is what I have found over the last 2 months.

http://www.toyotagtturbo.com/forums...Diagnosis-codes!-A-Guide!&p=953610#post953610

 

[starletsam]

on a manual GT i get about 450km per full tank of fuel and thats when driving it like a grandad best i got was 470km.with a bit of mixed driving i usually see around 380-400 and this is running a TD04 set up on 0.7 bar standard ECU.good or bad?

 

[chrisinflight]

That is really bad Chris! I would get the same mileage if I was getting 7K rpm everytime I drive a car!
I've got 180 miles (291 km) per £35 this week - about 27L. = 30 MPG! And that is AN AUTO - not to mention cracked mani and blown mani to turbo gasket! Most of the time I use normal mode and when in city use manu mode!

Did you put the cardboard in front of the radiator? I must admit short journeys on my car are horrible as well - I drive on average 16 miles per journey and around 35 a day!
I'd say there is definitely something wrong with your car if you drive it steady and get such MPG.

Yes, I agree with you there. As said before it`s not much better than the 3.0 td hilux I had before! I have`nt blocked the rad. with card-board- it reaches operating temp. within about 2 miles- 5 min. and the fan sometimes comes on after idling at the end of my short journey indicating it`s warm enough. It`s not using oil or water and is fully serviced- even new rad. I didn`t change the lambda sensor yesterday as I need a 20mm deep socket? and I`ve only up to 19mm.
I estimate all the easy steady driving with O/D on and MANU on has only brought the mileage up from 220km to 260km. That`s from full to reserve light.
Oh dear! Can a faulty lambda-sensor cause such bad mileage?
cheers,
chris

 

[Paul_JJ]

on a manual GT i get about 450km per full tank of fuel and thats when driving it like a grandad best i got was 470km.with a bit of mixed driving i usually see around 380-400 and this is running a TD04 set up on 0.7 bar standard ECU.good or bad?

Very good! Anything around 30mpg is brilliant for a Starlet! It's fantastic MPG for any sports car - try Mitsubishi EVO or something like that - you won't get more than 15-20mpg no way!

 

[Paul_JJ]

Yes, I agree with you there. As said before it`s not much better than the 3.0 td hilux I had before! I have`nt blocked the rad. with card-board- it reaches operating temp. within about 2 miles- 5 min. and the fan sometimes comes on after idling at the end of my short journey indicating it`s warm enough. It`s not using oil or water and is fully serviced- even new rad. I didn`t change the lambda sensor yesterday as I need a 20mm deep socket? and I`ve only up to 19mm.
I estimate all the easy steady driving with O/D on and MANU on has only brought the mileage up from 220km to 260km. That`s from full to reserve light.
Oh dear! Can a faulty lambda-sensor cause such bad mileage?
cheers,
chris

I don't know about a lambda sensor - I would've thought You would get an Engine Management light ON if it was faulty!
If you drive a short distance only - try putting a cardboard in front (half size of the radiator) it will heat up quicker thus consuming less petrol - I drive with a small cardboard since Late November! Without a cardboard my radiator is just warm - after 16 miles drive, not even hot.....

You've got to have something wrong with the car, keep looking! I don't think it's a sensor you normally get a light! What mods have you got by the way? Have you tried to reset the ECU and see if it helps? Disconnect the battery for a while, see if it changes anything! How old is your car by the way and what is the mileage?

 

[Paul_JJ]

Thank you Paul, from the way the car is acting I suspect it is the No. 1 solenoid - shift. Additionally, I think that driving with Manu - ON, Turbo - LOW gives the best millage. Since, the O2 Sensor - first one at Manifold would see more O2 in the exhaust on HIGH boost and add more fuel to the mix. Thus leading to worst millage. That is what I have found over the last 2 months.

No problem mate! Feel free to rep. me -)

High Boost is better for the fuel economy - I've driven with both for many miles! If you don't go hard on the gas you will see the high boost would be more economical!

 

[chrisinflight]

I don't know about a lambda sensor - I would've thought You would get an Engine Management light ON if it was faulty!
If you drive a short distance only - try putting a cardboard in front (half size of the radiator) it will heat up quicker thus consuming less petrol - I drive with a small cardboard since Late November! Without a cardboard my radiator is just warm - after 16 miles drive, not even hot.....

You've got to have something wrong with the car, keep looking! I don't think it's a sensor you normally get a light! What mods have you got by the way? Have you tried to reset the ECU and see if it helps? Disconnect the battery for a while, see if it changes anything! How old is your car by the way and what is the mileage?

Hi Paul, The car is a 1995 GT with 106000 km stock standard- no mods- still the original exhaust. No warning lights on dash. Battery has been disconnected to reset the ECU. I took actual mileage readings of 26mpg a month or so ago. Thats on short hilly journeys with temps. hovering around zero. If you say 30 mpg is good, I`m sure I can achieve that in summer and more motorway driving? 4 mpg down could be the result of short, cold, hilly journeys? Thanks for all the advice so far.
cheers,
chris

 

[Paul_JJ]

Hi Paul, The car is a 1995 GT with 106000 km stock standard- no mods- still the original exhaust. No warning lights on dash. Battery has been disconnected to reset the ECU. I took actual mileage readings of 26mpg a month or so ago. Thats on short hilly journeys with temps. hovering around zero. If you say 30 mpg is good, I`m sure I can achieve that in summer and more motorway driving? 4 mpg down could be the result of short, cold, hilly journeys? Thanks for all the advice so far.
cheers,
chris

Chris,

On short journeys 26 mpg is OK, it does drink a lot when the engine is cold! But 220 km per tank is 16.5 MPG! Well you should get 30mpg no matter the weather as Long as you drive for longer than 20 min every time you start the engine and most of the time on the A roads or the Motorway, assuming of course you don't exceed 3K rpm!

 

[koolgtstarlet]

I will try what what you suggest -- using high boost. However, for all that I have seen on this topic, it has much to do with the temperature in that geographic region and the height above sea level. Colder part of the world at sea level the air is denser and in hotter parts the opposite. Also, the octane grade of fuel being used. Given the the driving style is gentle, the mileage per tank of gas for me is 220-250Km if I see 300 KM I might die much less in the 400's.

 

[Rev]

Given the the driving style is gentle, the mileage per tank of gas for me is 220-250Km if I see 300 KM I might die much less in the 400's.

I've noticed I'm using about 1- 2mpg more since I turned up the idle ( auto box ) from 900 to 1300. I do have a turbo timer but the truth is the car picks up much better as it goes to 3000 rpm more easily so I put my foot down compared to before I was revving to about 2500 rpm .

 

[Paul_JJ]

I've noticed I'm using about 1- 2mpg more since I turned up the idle ( auto box ) from 900 to 1300. I do have a turbo timer but the truth is the car picks up much better as it goes to 3000 rpm more easily so I put my foot down compared to before I was revving to about 2500 rpm .

Mine is 750 RPM idle - this is how it should be by default -)

Have you tried to put in D, hold the brakes with left foot, rev up to 3K and let go the brakes?????