Celica Engine Settings

I have a 1995 ST 202 Celiac 2L auto JAP import. I have only had this a few
weeks but it seems to be doing very few miles to a gallon of fuel. As far as
I can see its about 26 and that's with nursing the throttle and low speeds.
I have to say it runs very well but if this is normal I wont be keeping it
long. I have just fitted a cam belt and I know the compressions are good.
It has new air filter and plugs. It seems that if you alter things on the
engine like the timing the ECU just corrects the settings as it makes no
difference to the running. So my question is how can I alter the fuel
settings to weaken it off a little. The only other thing that came to mind
was the Lambda sensor.Can this be checked as it makes no difference if its
connected or not.

"Ken" <kennethbooth@tiscali.co.uk> wrote in message
news:42c2d4ba$1_2@mk-nntp-2.news.uk.tiscali.com...[color=blue]
>I have a 1995 ST 202 Celiac 2L auto JAP import. I have only had this a few
>weeks but it seems to be doing very few miles to a gallon of fuel. As far
>as I can see its about 26 and that's with nursing the throttle and low
>speeds. I have to say it runs very well but if this is normal I wont be
>keeping it long. I have just fitted a cam belt and I know the compressions
>are good. It has new air filter and plugs. It seems that if you alter
>things on the engine like the timing the ECU just corrects the settings as
>it makes no difference to the running. So my question is how can I alter
>the fuel settings to weaken it off a little. The only other thing that
>came to mind was the Lambda sensor.Can this be checked as it makes no
>difference if its connected or not.[/color]

26 miles per gallons sounds about right for a Celica with a 2 liter engine -
I doubt if you can improve it much. If the Lambda sensor (O2 sensor) is
disconnected, I would think that a check engine light would appear unless
the ECU is bad or the check engine light itself is not functioning.
--
Ray O
correct the return address punctuation to reply

On Wed, 29 Jun 2005 13:10:06 -0500, Ray O wrote:
[color=blue]
>
> "Ken" <kennethbooth@tiscali.co.uk> wrote in message
> news:42c2d4ba$1_2@mk-nntp-2.news.uk.tiscali.com...[color=green]
>>I have a 1995 ST 202 Celiac 2L auto JAP import. I have only had this a few
>>weeks but it seems to be doing very few miles to a gallon of fuel. As far
>>as I can see its about 26 and that's with nursing the throttle and low
>>speeds. I have to say it runs very well but if this is normal I wont be
>>keeping it long. I have just fitted a cam belt and I know the compressions
>>are good. It has new air filter and plugs. It seems that if you alter
>>things on the engine like the timing the ECU just corrects the settings as
>>it makes no difference to the running. So my question is how can I alter
>>the fuel settings to weaken it off a little. The only other thing that
>>came to mind was the Lambda sensor.Can this be checked as it makes no
>>difference if its connected or not.[/color]
>
> 26 miles per gallons sounds about right for a Celica with a 2 liter engine -
> I doubt if you can improve it much. If the Lambda sensor (O2 sensor) is
> disconnected, I would think that a check engine light would appear unless
> the ECU is bad[/color]

And this would result in poor fuel economy.

You say it's an auto? I would expect at MOST 29MPG. You're right in the
ballpark.
[color=blue]
> or the check engine light itself is not functioning.[/color]

Now you have pulled the O2 sensor lead the ECU will have stored a bad
sensor code for it, and will be running in open loop all the time.
Reset the ECU by pulling out the main EFI fuse under the bonnet for a
while, sticking it back in and going for a nice drive. But 26 isnt far
wrong on these, with the auto box.

J

Ken wrote:[color=blue]
> I have a 1995 ST 202 Celiac 2L auto JAP import. I have only had this a few
> weeks but it seems to be doing very few miles to a gallon of fuel. As far as
> I can see its about 26 and that's with nursing the throttle and low speeds.
> I have to say it runs very well but if this is normal I wont be keeping it
> long. I have just fitted a cam belt and I know the compressions are good.
> It has new air filter and plugs. It seems that if you alter things on the
> engine like the timing the ECU just corrects the settings as it makes no
> difference to the running. So my question is how can I alter the fuel
> settings to weaken it off a little. The only other thing that came to mind
> was the Lambda sensor.Can this be checked as it makes no difference if its
> connected or not.[/color]

Ken wrote:[color=blue]
>It seems that if you alter things on the
> engine like the timing the ECU just corrects the settings as it makes no
> difference to the running.[/color]

BASE timing can be altered, but the ECU will then adjust to suit so it
makes little difference unless you are near the knock point.
[color=blue]
>So my question is how can I alter the fuel
> settings to weaken it off a little.[/color]

You cant, its entirely ECU controlled, even the idle speed.
[color=blue]
> The only other thing that came to mind
> was the Lambda sensor.Can this be checked as it makes no difference if its
> connected or not.[/color]

See earlier reply.

You have checked for error codes havent you? As these can cause poor
economy if the car is in limp mode. Theres info on how to do it at
[url]www.st205.net[/url], its for the alltrac turbo version but the process is the
same and most of the codes are similar IIRC.

J