90 Accord hard starting

Atmospheric Pressure can be replaced???? I don't know. I have not heard
of such sensor.
Thanks I will check it out.

If always drive in high altitude suitation, you neeed to adjust the idle
speed to compensate. The idle speed screw is on the throttle body.


"'Curly Q. Links'" > wrote in message
...
> wrote:
> >
> > My car does not run well on uphill driving. Sometimes it climbs fine.
> > Sometimes
> > it doesn't. I think it's has to do with humidity of atmosphere. The air
> > going into
> > engine is not constant. Some sea level it's ok and other sea level the
> > air is not going
> > well so the engine hesitate. I don't know what to do about.
>
> =========================
>
>
> If it's also hard to pass on level highway (sputtering), it's probably
> time for a fuel filter. It manifests when fuel flow is highest. Run a
> can of injector cleaner through and see if everything clears up.
> Simplest.
>
> 'Curly'

"Eric" > wrote in
:

> If always drive in high altitude suitation, you neeed to adjust the
> idle speed to compensate. The idle speed screw is on the throttle
> body.


***WRONG***

This is NOT the reason you adjust the idle speed. The engine management
system compensates for altitude changes automatically.


--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

You sure this isn't outdated advice?

I moved from sea level to a mile high with my 91 pgm-fi Civic LX manual
transmission a few years ago. I didn't touch anything, based on my reading
that the car's ECU blah blah makes the appropriate adjustments. Idle is
fine; same ol' same ol'. Mileage continues at 40+ mpg for 3/4s of the year.

"Eric" > wrote
> If always drive in high altitude suitation, you neeed to adjust the idle
> speed to compensate. The idle speed screw is on the throttle body.
>
>
> "'Curly Q. Links'" > wrote
> > wrote:
> > >
> > > My car does not run well on uphill driving. Sometimes it climbs fine.
> > > Sometimes
> > > it doesn't. I think it's has to do with humidity of atmosphere. The
air
> > > going into
> > > engine is not constant. Some sea level it's ok and other sea level
the
> > > air is not going
> > > well so the engine hesitate. I don't know what to do about.
> >
> > =========================
> >
> >
> > If it's also hard to pass on level highway (sputtering), it's probably
> > time for a fuel filter. It manifests when fuel flow is highest. Run a
> > can of injector cleaner through and see if everything clears up.
> > Simplest.
> >
> > 'Curly'
>
>

"Elle" > wrote in
ink.net:

> You sure this isn't outdated advice?


If it's "outdated", then it's oudated enough to date back to the '50s. Cars
have had automatic altitude compensator mechanisms at least as far back as
then.


--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Please obtain the original service manual and you will undersdtand 1991
Accord don't have altitude compensator mechanisms. You need to adjust
according to the factory manual.


"TeGGeR®" > wrote in message
...
> "Elle" > wrote in
> ink.net:
>
> > You sure this isn't outdated advice?
>
>
> If it's "outdated", then it's oudated enough to date back to the '50s.
Cars
> have had automatic altitude compensator mechanisms at least as far back as
> then.
>
>
> --
> TeGGeR®
>
> The Unofficial Honda/Acura FAQ
> www.tegger.com/hondafaq/

One advice, you can spray carbon cleaner to clean the throttle body and
cylinder head from air intake.


"Eric" > wrote in message
...
> Please obtain the original service manual and you will undersdtand 1991
> Accord don't have altitude compensator mechanisms. You need to adjust
> according to the factory manual.
>
>
> "TeGGeR®" > wrote in message
> ...
> > "Elle" > wrote in
> > ink.net:
> >
> > > You sure this isn't outdated advice?
> >
> >
> > If it's "outdated", then it's oudated enough to date back to the '50s.
> Cars
> > have had automatic altitude compensator mechanisms at least as far back
as
> > then.
> >
> >
> > --
> > TeGGeR®
> >
> > The Unofficial Honda/Acura FAQ
> > www.tegger.com/hondafaq/
>
>

"Eric" > wrote in
:

> Please obtain the original service manual and you will undersdtand
> 1991 Accord don't have altitude compensator mechanisms. You need to
> adjust according to the factory manual.


The Honda engine management system corrects for changes in air volume by
comparing the inputs from the:
Pressure Air (atmospheric pressure) Sensor
Manifold Absolute Pressure Sensor
Temperature (Air) Sensor

Using these it calculates the actual air volume entering the engine. If the
volume should decline, as it would at higher altitudes, the ECU will
compensate by reducing fuel delivery, and then maintain correct idle speed
using the Crankshaft Position Sensor.

The actual dedicated altitude compensation devices that were installed on
carbureted cars are irrelevant in this age of computerized engine
management.



--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

My car is fuel injection. Of 3 sensors you mentioned, I could have
problem of one of 3 sensors or
2 or all 3 that sometimes not easy to climb on uphill driving. Since
sensor is an electronic device, my problem could be in malfuncationed
electronic device.

> wrote in message oups.com...

> My car is fuel injection. Of 3 sensors you mentioned, I could have
> problem of one of 3 sensors or
> 2 or all 3 that sometimes not easy to climb on uphill driving. Since
> sensor is an electronic device, my problem could be in malfuncationed
> electronic device.

>>Pressure Air (atmospheric pressure) Sensor

This is inside the cabin and well protected. Never seen one die.

>>Manifold Absolute Pressure Sensor

This is reliable device inside the vacuum box with a vacuum hose
running to the throttle body and electrical wires to the ECU. The
hose can be inspected.

>>Temperature (Air) Sensor

This is inside the throttle body, prone to buildup crud or destroyed
by other means. Resistance changes based on air temperatures. You
can compare it to a chart. Maybe Teggar has a chart for you.