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Discussion Starter #1
My 97 Camry 4 cyl gets about 24 MPG all around driving. How does this
compare to others? It seems less than the 94 I used to have. It has
103K and I just changed the spark plugs and air filter to see if that
would make a difference. I can't say I notice much change. I'm not a
lead foot or have jackrabbit starts either. No, I have not had it to
the dealer for a tuneup; what else can I do myself?

My wife has been driving this car for a couple of years and she is much
heavier on the accelerator than I am. Is it true about cars "learning"
driving habits and adapting to their drivers? That seems silly to me
but some of my co-workers swear it's true.

--
No matter what happens someone will find a way to take it too seriously.
 
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Discussion Starter #2
How old is your timing belt , a stretched belt retards timing , reducing
milage and power, Timing is a good place to start.
 
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"badgolferman" <[email protected]> wrote in message
news:[email protected]
> My 97 Camry 4 cyl gets about 24 MPG all around driving. How does this
> compare to others? It seems less than the 94 I used to have. It has
> 103K and I just changed the spark plugs and air filter to see if that
> would make a difference. I can't say I notice much change. I'm not a
> lead foot or have jackrabbit starts either. No, I have not had it to
> the dealer for a tuneup; what else can I do myself?
>
> My wife has been driving this car for a couple of years and she is much
> heavier on the accelerator than I am. Is it true about cars "learning"
> driving habits and adapting to their drivers? That seems silly to me
> but some of my co-workers swear it's true.


opinion only:

There are differing types of 'intelligent transmissions'. The more modern
ones have variable gear- ratios (must work on some sort of DAF belt-drive
(been around for eons) with infinately variable pulleys?),..the lessor types
tending to remember your throttle settings and so adjusting the trans-shift
points (similar to the 'power/economy' button on trans-shifters}. Ultimately
tho, this shouldn't have a dramatic effect on economy.

If your driving is 3/4 urban-city street, then 24 mpg is reasonable imho. If
it were the reverse, ie mostly hiway,..then its way to low.



Jason
 
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Discussion Starter #4
Some areas winter gas formulations give less milage.
I notice a big difference when I switch motor, trans, and differential
to Mobil synthetic.
 
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Discussion Starter #5
Jason James wrote:
> "badgolferman" <[email protected]> wrote in message
> news:[email protected]
>> My 97 Camry 4 cyl gets about 24 MPG all around driving. How does
>> this compare to others? It seems less than the 94 I used to have.
>> It has 103K and I just changed the spark plugs and air filter to see
>> if that would make a difference. I can't say I notice much change.
>> I'm not a lead foot or have jackrabbit starts either. No, I have
>> not had it to
>> the dealer for a tuneup; what else can I do myself?
>>
>> My wife has been driving this car for a couple of years and she is
>> much heavier on the accelerator than I am. Is it true about cars
>> "learning" driving habits and adapting to their drivers? That seems
>> silly to me
>> but some of my co-workers swear it's true.

>
> opinion only:
>
> There are differing types of 'intelligent transmissions'. The more
> modern ones have variable gear- ratios (must work on some sort of DAF
> belt-drive (been around for eons) with infinately variable
> pulleys?),..the lessor types tending to remember your throttle
> settings and so adjusting the trans-shift points (similar to the
> 'power/economy' button on trans-shifters}. Ultimately tho, this
> shouldn't have a dramatic effect on economy.
>
> If your driving is 3/4 urban-city street, then 24 mpg is reasonable
> imho. If it were the reverse, ie mostly hiway,..then its way to low.
>
> Jason


Jason ... With only a couple of recent exceptions, "intelligent" automatic
transmissions still use planetary gearsets and as such, are not CVT
automatics.
--

- Philip
 

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Gas has a big effect. Don't use any Blue Planet gas. The high ethanol content causes power los. It burns, but no real heat is created by it. Don't get gas from Holiday, or Super America. Their gas is watered down (they get the post line flushing gas from the refinery). Fleat farm are good. BP is good.

Keep the RPM's low. I found I can get 27mpg in my '92 V6 (with 207k) if I keep the RPM's under 2,500. 2,500RPM is still high enough to get up to 60mph.
 
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Discussion Starter #7
m Ransley wrote:

> Some areas winter gas formulations give less milage.
> I notice a big difference when I switch motor, trans, and
> differential to Mobil synthetic.


You may be right about the winter gas. It seems I am not the only one
noticing this. Some of my friends say the same thing.

--
No matter what happens, someone will find a way to take it too
seriously.
 
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Discussion Starter #8
Also cold winter weather lowers my milage apx 4 mpg.
But checking timing is a quick 5 min job that will give major
improvements if it is off by 2-3 degrees, it increased my milage by 4
mpg on a new belt the mechanic forgot to check
 

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m Ransley said:
Also cold winter weather lowers my milage apx 4 mpg.
But checking timing is a quick 5 min job that will give major
improvements if it is off by 2-3 degrees, it increased my milage by 4
mpg on a new belt the mechanic forgot to check

^
This is an extremely band statement and should not be taken as fact.


4mpg has tons of variables. And that number is per vehicle. It also depends on the ECU. The ECU in a Subaru is corrective. When the O2 sensor in the exhaust manifold senses the cold, it causes it to run rich the the assumption that it is still warming up. However older Camrys do not have a corrective ECU. So they do not run rich past warm up (which is based on the engine temp sensor). Newer ones may have it, I am not 100% sure. However depending on the temp outside is how long the O2 sensor assumes that it is cold. There are way too many variables to assume 4mpg.
 
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Discussion Starter #10
Smoking tires. My statement is fact, do you live where it gets to -20f.
Cold components have more friction and take much longer to warm up.
Often My car is not warmed up till I return from short tips to the
store. I know of nobody that doesnt suffer from winter cold milage
reduction here. The timing is also fact, no ECU will compensate for
this.
 
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Discussion Starter #11
SmokingTiresV6 wrote:
> m Ransley Wrote:
>> Also cold winter weather lowers my milage apx 4 mpg.
>> But checking timing is a quick 5 min job that will give major
>> improvements if it is off by 2-3 degrees, it increased my milage by 4
>> mpg on a new belt the mechanic forgot to check

>
>
> ^
> This is an extremely band statement and should not be taken as fact.
>
>
> 4mpg has tons of variables. And that number is per vehicle. It also
> depends on the ECU. The ECU in a Subaru is corrective. When the O2
> sensor in the exhaust manifold senses the cold, it causes it to run
> rich the the assumption that it is still warming up. However older
> Camrys do not have a corrective ECU. So they do not run rich past
> warm up (which is based on the engine temp sensor). Newer ones may
> have it, I am not 100% sure. However depending on the temp outside
> is how long the O2 sensor assumes that it is cold. There are way too
> many variables to assume 4mpg.


The above statement by "Smoking Tires V6" has numerous debatable points and
an outright inaccuracies.

"Older Camrys do not have a "corrective" ECU" ON WHAT PLANET? From the
inception of feedback carbureted Camrys of the early 1980's and all of the
subsequent fuel injected Camrys, the fuel feedback systems are "corrective"
for engine and intake air temperature (and many other inputs).

" However depending on the temp outside is how long the O2 sensor assumes
that it is cold." THIS passage suggests you believe the O2 sensor is
ambient air temperature sensitive. It is not. It is exhaust temperature
sensitive in that it must be heated to at least 550 degrees before it will
produce an ECU usable input.
--

- Philip
 
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Discussion Starter #12
m Ransley wrote:
> Smoking tires. My statement is fact, do you live where it gets to
> -20f. Cold components have more friction and take much longer to warm
> up. Often My car is not warmed up till I return from short tips to the
> store. I know of nobody that doesnt suffer from winter cold milage
> reduction here. The timing is also fact, no ECU will compensate for
> this.


The ECU does refer to a basic timing matrix before executing a 'calculated'
ignition timing. Ambient air temperature and coolant temperature are only
two of many inputs that the ECU uses to arrive at a 'calculated ignition
point.
--

- Philip
 
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