1988 Honda Accord Lxi rev'ing Up and Down

Got a question maybe someone can answer...

My 88 Honda Accord Lxi with 200K plus milage started rev'ing up and down
after warming up. I thought maybe the vacuum adv. on the distributor
might be bad, but verifing timing (pulling hoses and blocking/ chk
timing) all are alright (car does not rev up and dwn when I do this).
But once I put the hoses back same thing. If I pull the hose closest to
the front end of the car, the engine stops rev'ing up and dwn. Another
thing I did is replacing the all hoses to vacuum adv, I disconnected the
power plug to the vacuum control module (left portion of firewall) and the
car stops rev'ing up and down. SUGGESTIONS????

 

Best I can think of: turn the heat to max and bleed coolant. Remove the
battery for a minute to reset ECU.

 

Best I can think of: turn the heat to max and bleed coolant. Remove the
battery for a minute to reset ECU.

 

ECU re-set is done by removing the ECU fuse for ten seconds. The fuse
is in the under hood fuse box.
See if there is something in the intake screen for the vacuum source in
the big box full of controls on the passenger side of the outer
firewall. (all the vac lines run to it)
Good Luck! bob

 

ECU re-set is done by removing the ECU fuse for ten seconds. The fuse
is in the under hood fuse box.
See if there is something in the intake screen for the vacuum source in
the big box full of controls on the passenger side of the outer
firewall. (all the vac lines run to it)
Good Luck! bob

 

I agree with the above suggestion to bleed the coolant. The most common
problem associated with the idle cycling up and down is usually due to a
lack of coolant flowing through the cold start valve. The valve is item
number 8 in this diagram http://tinyurl.com/xj18. If the valve doesn't warm
up as the engine warms up (from coolant flowing through the bottom part),
the PGMFI system will misinterpret the condition and idle cycling results.
The first thing to due is to check the valve and make sure that the lower
part of the valve gets hot as the engine warms up. If the valve doesn't get
hot, try bleeding the coolant and make sure that coolant is flowing through
the valve. You can double check the valve as a source of the cycling by
removing the two screws from the top along with the oval shaped plate and
push down on the inner valve/plunger in the center. The cycling should stop
if the valve is the problem. If the valve is getting hot and pushing the
inner plunger down stops the cycling, then the valve likely needs to be
replaced.

Eric

 

I agree with the above suggestion to bleed the coolant. The most common
problem associated with the idle cycling up and down is usually due to a
lack of coolant flowing through the cold start valve. The valve is item
number 8 in this diagram http://tinyurl.com/xj18. If the valve doesn't warm
up as the engine warms up (from coolant flowing through the bottom part),
the PGMFI system will misinterpret the condition and idle cycling results.
The first thing to due is to check the valve and make sure that the lower
part of the valve gets hot as the engine warms up. If the valve doesn't get
hot, try bleeding the coolant and make sure that coolant is flowing through
the valve. You can double check the valve as a source of the cycling by
removing the two screws from the top along with the oval shaped plate and
push down on the inner valve/plunger in the center. The cycling should stop
if the valve is the problem. If the valve is getting hot and pushing the
inner plunger down stops the cycling, then the valve likely needs to be
replaced.

Eric

 

Indian Summer,

To clarify, I think you mean to bleed the AIR that's trapped in the
cooling system (at the provided nipple) rather than DRAIN the coolant.
Some folks wouldn't know that there is a difference.

'Curly'

------------------------------

 

Indian Summer,

To clarify, I think you mean to bleed the AIR that's trapped in the
cooling system (at the provided nipple) rather than DRAIN the coolant.
Some folks wouldn't know that there is a difference.

'Curly'

------------------------------

 

Appreciate All the help!! Will try and see what happens.

 

Appreciate All the help!! Will try and see what happens.

 

Had this problem on a 1992 Honda Accord. The idle air screw on the
throttle body had loosened causing the engine to rev up. The computer
would then try to bring the idle down, the net result was a flucuation
in idle between 1,000 and 1,500 rpm. So you might want to check the
screw (was on left side of throttle body opening on the '92), I think
the normal idle speed should be around 750rpm. I just turned the
screw clockwise until I reached that rpm and the revving stopped.

Good luck.

 

Had this problem on a 1992 Honda Accord. The idle air screw on the
throttle body had loosened causing the engine to rev up. The computer
would then try to bring the idle down, the net result was a flucuation
in idle between 1,000 and 1,500 rpm. So you might want to check the
screw (was on left side of throttle body opening on the '92), I think
the normal idle speed should be around 750rpm. I just turned the
screw clockwise until I reached that rpm and the revving stopped.

Good luck.

 

(John W.) wrote in

Figured it out!!!! The EACV was gummed up (to use that term), cleaned
with carburator/choke cleaner and put back on. Car ran Great!!!!
Thanks for all the tips and tricks

 

(John W.) wrote in

Figured it out!!!! The EACV was gummed up (to use that term), cleaned
with carburator/choke cleaner and put back on. Car ran Great!!!!
Thanks for all the tips and tricks

 

Can you interpret 'EACV' for me? I own an LX-i, and would like tocheck
this on my car. Thanks, bob

 

Can you interpret 'EACV' for me? I own an LX-i, and would like tocheck
this on my car. Thanks, bob

 

EACV--> Electronic Air Control Valve. It is located on the front side
of the PGM-FI. It has a power connector top right and a inlet out let
hoses on the bottom side of it. It is held on by two bolts. The right
one is easy to take off, the left will hit the vacuum rail.

 

EACV--> Electronic Air Control Valve. It is located on the front side
of the PGM-FI. It has a power connector top right and a inlet out let
hoses on the bottom side of it. It is held on by two bolts. The right
one is easy to take off, the left will hit the vacuum rail.

 

Thanks! bob