94 accord High idle when driving, low idle when stopped.

I own a 94 accord ex with 300 000 km. When I am driving and press in
the clutch and coast, my rpms are generally 1800-2500. When I come to
a complete stop, they drop down and almost stall before bumpimg up to
about 800rpm. While I am stopped, it will continue going up and down,
some times to the point of actually stalling.

The engine reads a EGR system error. I took off the valve and
manually depressed it. When I put it back on, I checked that vacuum
stalls the engine and it does. This helped a little, but not much.

And now, I have another error, this time with the O2 sensor.

As well after noticing this problem, when the enginer is around 2200
rpms, it sometimes stumbles, but feels fine when I give it some gas.

I have noticed that the coolant in the reservoir was low, but I added
some and it didn't seem to help.

Any help would be greatly appreciated.

Thanks,

Matt.

 

need to make sure the coolant is full to the top of the radiator &
"burped" to be certain there's no air locks near the coolant temp sensor.

any other error codes? which codes exactly?

regarding coasting behavior, first, check clutch operation. if you're
coasting with the clutch pedal down, it should idle as per the vehicle
being stationary, not at elevated rpm's. higher rpm's suggest that the
clutch is not disengaging properly. likewise, if it almost stalls on
stopping, it could be the clutch plate breaking loose just before being
free to idle. do you notice it being hard to shift? what happens if
you try starting it with a gear engaged, but clutch pedal down? any
torque or lurch?

regarding other causes, check all vacuum lines, including the brake
booster. oxygen sensor is a simple fix. check the eacv, the idling air
circuit. also, if the distributor has been taken off at all, check the
timing as that can make the vehicle hesitate at low rpm's. if this is
the same vehicle as per your timing belt question, you may have to
replace the pulley wheel to get the timing marks back.

 

j

THanks for the reply.

The rad seems full to the top of fluid. My clutch was replaced 4
months ago, and it worked fine afterwards.
I also don't believe it is the clutch, because when I am driving
and coast, the rpms go up, but I am able to lower the rpms by engaging
the clutch.

As well, when I come to a complete stop, the rpms drop from the
2500 (while coasting) and then almost stall, then recover and is rough
for a couple seconds and then almost stalls again.

When I start it in gear, with clutch down there is no lurch or
movement.

The codes are 1 and 12.

I don't see any problems with the vacuum lines. (and yup, It is my
timing belt question as well)

All of my problems started after I replaced the clutch, and then
could not start my car. I waited a day and than it started no
problem. And after that it would not start. It cranked, had NO error
codes.
I posted for help here and someone replied that he had had a
similar problem and that it was a fuel injector stuck open and
therefore the engine was flooded. Sure enough when I tried to start
the car with the gas pedal depressed (for flooding) VRoooomm!
Then I put some fuel injector cleaner in my gas tank. I noticed an
improvement in acceleration, but almost immediately a code 12 (egr
system) enging light came on.

THanks again for your help- I could sure use it!

 

check the ground connections!

1 & 12 are what you say. 1 is easy to fix. 12, not so sure. i've
never had a problem with any of my hondas for that so don't have direct
experience to advise you other than what's in the manual - which you
already seem to have. i can only suggest you follow honda's diagnostic,
if the ground lead check does not fix it.

regarding problems /after/ changing the clutch, you've got to look at
that as a likely cause in some way. regarding high idle while rolling &
stumbling when braking, i stand by what i say about the clutch not
disengaging properly. i've seen those symptoms in an automatic where
the lockup clutch was not disengaging - it's somewhat coincidental that
a clutch change on this vehicle has this same effect. was the pilot
bearing changed or damaged in some way? without having the vehicle in
front of me, it's hard to be more constructive.