Jim Yanik said:
>
> Open loop makes the fuel-air mix richer than optimal(for emissions) ALL the
> time,just as it does until the engine warms up to operating temperature.You
> have to avoid a too-lean condition in -all- operating conditions,to avoid
> damaging the engine.
>
> Closed loop optimizes the fuel-air mix for the leanest possible mix -
> without- risking a too-lean condition that could burn a piston or make the
> motor run too hot.It minimizes the extra hydrocarbons (rich exhaust)that
> the cat-converter has to burn up,for best emissions.
>
> You have a open-loop at the start because the catalytic has not warmed up
> yet,nor has the motor.(coolant,plugs)
>


This makes a lot of sense.. So a sensor retrofit would be useful then?


> Some adventurous soul here could disconnect their O2 sensor and see if the
> ECU then flashes the "check engine" light. A brief test.


If only some kind soul would try this... But I think the ECU would
just throw a CEL. I'll look at the ECU pinouts today, and post back.

 

"sharx333" <emil.santos@gmail.com> wrote in
news:1158098160.761918.270830@p79g2000cwp.googlegr oups.com:

>
> Jim Yanik said:
>>
>> Open loop makes the fuel-air mix richer than optimal(for emissions)
>> ALL the time,just as it does until the engine warms up to operating
>> temperature.You have to avoid a too-lean condition in -all- operating
>> conditions,to avoid damaging the engine.
>>
>> Closed loop optimizes the fuel-air mix for the leanest possible mix -
>> without- risking a too-lean condition that could burn a piston or
>> make the motor run too hot.It minimizes the extra hydrocarbons (rich
>> exhaust)that the cat-converter has to burn up,for best emissions.
>>
>> You have a open-loop at the start because the catalytic has not
>> warmed up yet,nor has the motor.(coolant,plugs)
>>
>
>
> This makes a lot of sense.. So a sensor retrofit would be useful then?

I doubt it would be worth the expense.
Considering you would have to change the ECU in addition. That's big bucks.
If you're looking for better gas mileage,changing your driving habits would
be far more productive,keeping your tires inflated properly.

>
>
>> Some adventurous soul here could disconnect their O2 sensor and see
>> if the ECU then flashes the "check engine" light. A brief test.
>
>
> If only some kind soul would try this... But I think the ECU would
> just throw a CEL.

It's supposed to;it's a failure of the O2 sensor(missing = "open"
sensor),and the control loop is no longer closed,emissions not controlled.

> I'll look at the ECU pinouts today, and post back.
>

Your car should have a *different ECU* if it does not have an O2 sensor.
Honda kept the same wiring harness for cost and simplicity,but the ECU
would have to have different programming to ignore the missing O2 sensor
and not flash the CEL.
Since Honda solders in their PROMs,ECUs are different.

--
Jim Yanik
jyanik
at
kua.net

 

"sharx333" <emil.santos@gmail.com> wrote in
news:1158098160.761918.270830@p79g2000cwp.googlegr oups.com:

>
> Jim Yanik said:
>>
>> Open loop makes the fuel-air mix richer than optimal(for emissions)
>> ALL the time,just as it does until the engine warms up to operating
>> temperature.You have to avoid a too-lean condition in -all- operating
>> conditions,to avoid damaging the engine.
>>
>> Closed loop optimizes the fuel-air mix for the leanest possible mix -
>> without- risking a too-lean condition that could burn a piston or
>> make the motor run too hot.It minimizes the extra hydrocarbons (rich
>> exhaust)that the cat-converter has to burn up,for best emissions.
>>
>> You have a open-loop at the start because the catalytic has not
>> warmed up yet,nor has the motor.(coolant,plugs)
>>
>
>
> This makes a lot of sense.. So a sensor retrofit would be useful then?

I doubt it would be worth the expense.
Considering you would have to change the ECU in addition. That's big bucks.
If you're looking for better gas mileage,changing your driving habits would
be far more productive,keeping your tires inflated properly.

>
>
>> Some adventurous soul here could disconnect their O2 sensor and see
>> if the ECU then flashes the "check engine" light. A brief test.
>
>
> If only some kind soul would try this... But I think the ECU would
> just throw a CEL.

It's supposed to;it's a failure of the O2 sensor(missing = "open"
sensor),and the control loop is no longer closed,emissions not controlled.

> I'll look at the ECU pinouts today, and post back.
>

Your car should have a *different ECU* if it does not have an O2 sensor.
Honda kept the same wiring harness for cost and simplicity,but the ECU
would have to have different programming to ignore the missing O2 sensor
and not flash the CEL.
Since Honda solders in their PROMs,ECUs are different.

--
Jim Yanik
jyanik
at
kua.net

 

"sharx333" <emil.santos@gmail.com> wrote in
news:1158098160.761918.270830@p79g2000cwp.googlegr oups.com:

>
> Jim Yanik said:
>>
>> Open loop makes the fuel-air mix richer than optimal(for emissions)
>> ALL the time,just as it does until the engine warms up to operating
>> temperature.You have to avoid a too-lean condition in -all- operating
>> conditions,to avoid damaging the engine.
>>
>> Closed loop optimizes the fuel-air mix for the leanest possible mix -
>> without- risking a too-lean condition that could burn a piston or
>> make the motor run too hot.It minimizes the extra hydrocarbons (rich
>> exhaust)that the cat-converter has to burn up,for best emissions.
>>
>> You have a open-loop at the start because the catalytic has not
>> warmed up yet,nor has the motor.(coolant,plugs)
>>
>
>
> This makes a lot of sense.. So a sensor retrofit would be useful then?

I doubt it would be worth the expense.
Considering you would have to change the ECU in addition. That's big bucks.
If you're looking for better gas mileage,changing your driving habits would
be far more productive,keeping your tires inflated properly.

>
>
>> Some adventurous soul here could disconnect their O2 sensor and see
>> if the ECU then flashes the "check engine" light. A brief test.
>
>
> If only some kind soul would try this... But I think the ECU would
> just throw a CEL.

It's supposed to;it's a failure of the O2 sensor(missing = "open"
sensor),and the control loop is no longer closed,emissions not controlled.

> I'll look at the ECU pinouts today, and post back.
>

Your car should have a *different ECU* if it does not have an O2 sensor.
Honda kept the same wiring harness for cost and simplicity,but the ECU
would have to have different programming to ignore the missing O2 sensor
and not flash the CEL.
Since Honda solders in their PROMs,ECUs are different.

--
Jim Yanik
jyanik
at
kua.net

 

> > Jim Yanik said:
>
> I doubt it would be worth the expense.
> Considering you would have to change the ECU in addition. That's big bucks.
> If you're looking for better gas mileage,changing your driving habits would
> be far more productive,keeping your tires inflated properly.
>


Thanks, jim. You make a good point.

I'm really curious about this "open" vs "closed" loop mode. Are we
greatly disadvantaged by always running in open loop? Or are we "lucky"
as TeGGer says? Can't an ECU run in closed loop using just MAP, TPS,
TA, etc sensors?

 

> > Jim Yanik said:
>
> I doubt it would be worth the expense.
> Considering you would have to change the ECU in addition. That's big bucks.
> If you're looking for better gas mileage,changing your driving habits would
> be far more productive,keeping your tires inflated properly.
>


Thanks, jim. You make a good point.

I'm really curious about this "open" vs "closed" loop mode. Are we
greatly disadvantaged by always running in open loop? Or are we "lucky"
as TeGGer says? Can't an ECU run in closed loop using just MAP, TPS,
TA, etc sensors?

 

> > Jim Yanik said:
>
> I doubt it would be worth the expense.
> Considering you would have to change the ECU in addition. That's big bucks.
> If you're looking for better gas mileage,changing your driving habits would
> be far more productive,keeping your tires inflated properly.
>


Thanks, jim. You make a good point.

I'm really curious about this "open" vs "closed" loop mode. Are we
greatly disadvantaged by always running in open loop? Or are we "lucky"
as TeGGer says? Can't an ECU run in closed loop using just MAP, TPS,
TA, etc sensors?

 

sharx333 wrote:
>>> Jim Yanik said:
>> I doubt it would be worth the expense.
>> Considering you would have to change the ECU in addition. That's big bucks.
>> If you're looking for better gas mileage,changing your driving habits would
>> be far more productive,keeping your tires inflated properly.
>>
>
>
> Thanks, jim. You make a good point.
>
> I'm really curious about this "open" vs "closed" loop mode. Are we
> greatly disadvantaged by always running in open loop? Or are we "lucky"
> as TeGGer says? Can't an ECU run in closed loop using just MAP, TPS,
> TA, etc sensors?
>
no, it needs to know "lambda", the actual ratio of fuel to air the
engine is experiencing. the only way to do that is with a sensor.
older sensors only detected what's called "stoichiometry", i.e. when the
mix is perfect. newer sensors are "broad band" and detect the range
typically sought, i.e. lambda from 0.8 to 1.2. [the former is lean, the
latter rich - and peak torque.] either way, a sensor allows the ecu to
tune the engine perfectly for its running conditions. closed loop is
the way to go.

if you want to retrofit, you could look at this as a science experiment
and buy a used ecu online from the states. they're typically in the $30
to $100 range for the standard models.

 

sharx333 wrote:
>>> Jim Yanik said:
>> I doubt it would be worth the expense.
>> Considering you would have to change the ECU in addition. That's big bucks.
>> If you're looking for better gas mileage,changing your driving habits would
>> be far more productive,keeping your tires inflated properly.
>>
>
>
> Thanks, jim. You make a good point.
>
> I'm really curious about this "open" vs "closed" loop mode. Are we
> greatly disadvantaged by always running in open loop? Or are we "lucky"
> as TeGGer says? Can't an ECU run in closed loop using just MAP, TPS,
> TA, etc sensors?
>
no, it needs to know "lambda", the actual ratio of fuel to air the
engine is experiencing. the only way to do that is with a sensor.
older sensors only detected what's called "stoichiometry", i.e. when the
mix is perfect. newer sensors are "broad band" and detect the range
typically sought, i.e. lambda from 0.8 to 1.2. [the former is lean, the
latter rich - and peak torque.] either way, a sensor allows the ecu to
tune the engine perfectly for its running conditions. closed loop is
the way to go.

if you want to retrofit, you could look at this as a science experiment
and buy a used ecu online from the states. they're typically in the $30
to $100 range for the standard models.

 

sharx333 wrote:
>>> Jim Yanik said:
>> I doubt it would be worth the expense.
>> Considering you would have to change the ECU in addition. That's big bucks.
>> If you're looking for better gas mileage,changing your driving habits would
>> be far more productive,keeping your tires inflated properly.
>>
>
>
> Thanks, jim. You make a good point.
>
> I'm really curious about this "open" vs "closed" loop mode. Are we
> greatly disadvantaged by always running in open loop? Or are we "lucky"
> as TeGGer says? Can't an ECU run in closed loop using just MAP, TPS,
> TA, etc sensors?
>
no, it needs to know "lambda", the actual ratio of fuel to air the
engine is experiencing. the only way to do that is with a sensor.
older sensors only detected what's called "stoichiometry", i.e. when the
mix is perfect. newer sensors are "broad band" and detect the range
typically sought, i.e. lambda from 0.8 to 1.2. [the former is lean, the
latter rich - and peak torque.] either way, a sensor allows the ecu to
tune the engine perfectly for its running conditions. closed loop is
the way to go.

if you want to retrofit, you could look at this as a science experiment
and buy a used ecu online from the states. they're typically in the $30
to $100 range for the standard models.

 

sharx333 wrote:
>>>Jim Yanik said:
>>
>>I doubt it would be worth the expense.
>>Considering you would have to change the ECU in addition. That's big bucks.
>>If you're looking for better gas mileage,changing your driving habits would
>>be far more productive,keeping your tires inflated properly.
>>
>
>
>
> Thanks, jim. You make a good point.
>
> I'm really curious about this "open" vs "closed" loop mode. Are we
> greatly disadvantaged by always running in open loop?

Well, it's worked for over 100 years... your average classic muscle car has
virtually nothing in the way of "engine management".

 

sharx333 wrote:
>>>Jim Yanik said:
>>
>>I doubt it would be worth the expense.
>>Considering you would have to change the ECU in addition. That's big bucks.
>>If you're looking for better gas mileage,changing your driving habits would
>>be far more productive,keeping your tires inflated properly.
>>
>
>
>
> Thanks, jim. You make a good point.
>
> I'm really curious about this "open" vs "closed" loop mode. Are we
> greatly disadvantaged by always running in open loop?

Well, it's worked for over 100 years... your average classic muscle car has
virtually nothing in the way of "engine management".

 

sharx333 wrote:
>>>Jim Yanik said:
>>
>>I doubt it would be worth the expense.
>>Considering you would have to change the ECU in addition. That's big bucks.
>>If you're looking for better gas mileage,changing your driving habits would
>>be far more productive,keeping your tires inflated properly.
>>
>
>
>
> Thanks, jim. You make a good point.
>
> I'm really curious about this "open" vs "closed" loop mode. Are we
> greatly disadvantaged by always running in open loop?

Well, it's worked for over 100 years... your average classic muscle car has
virtually nothing in the way of "engine management".

 

Matt Ion <soundy@moltenimage.com> wrote in
newsaVNg.536500$iF6.347125@pd7tw2no:

> sharx333 wrote:
>>>>Jim Yanik said:
>>>
>>>I doubt it would be worth the expense.
>>>Considering you would have to change the ECU in addition. That's big
>>>bucks. If you're looking for better gas mileage,changing your driving
>>>habits would be far more productive,keeping your tires inflated
>>>properly.
>>>
>>
>>
>>
>> Thanks, jim. You make a good point.
>>
>> I'm really curious about this "open" vs "closed" loop mode. Are we
>> greatly disadvantaged by always running in open loop?
>
> Well, it's worked for over 100 years... your average classic muscle
> car has virtually nothing in the way of "engine management".
>
>
>
>

Often,those "classic muscle cars" would not run well in other than optimal
weather or driving conditions.

--
Jim Yanik
jyanik
at
kua.net

 

Matt Ion <soundy@moltenimage.com> wrote in
newsaVNg.536500$iF6.347125@pd7tw2no:

> sharx333 wrote:
>>>>Jim Yanik said:
>>>
>>>I doubt it would be worth the expense.
>>>Considering you would have to change the ECU in addition. That's big
>>>bucks. If you're looking for better gas mileage,changing your driving
>>>habits would be far more productive,keeping your tires inflated
>>>properly.
>>>
>>
>>
>>
>> Thanks, jim. You make a good point.
>>
>> I'm really curious about this "open" vs "closed" loop mode. Are we
>> greatly disadvantaged by always running in open loop?
>
> Well, it's worked for over 100 years... your average classic muscle
> car has virtually nothing in the way of "engine management".
>
>
>
>

Often,those "classic muscle cars" would not run well in other than optimal
weather or driving conditions.

--
Jim Yanik
jyanik
at
kua.net