HONDA ACCORD HELP -- ROUGH IDLE

Hello,

My 1992 Honda Accord EX, 5sp suddenly started to skip during idle.
Otherwise the car runs fine, delivers normal power and mileage at road
speed. The car is serviced routinely. I replaced the plugs and
ignition wires without effect. What next? Can the Ox sensor(s) cause
rough idle? The vehicle has 398K miles. Mostly original equipment.

Please email:

Thanks,
Phil

 

Connect a timing gun between the coil and distributor. With a quality gun,
you should see continous flashes at lowest idle. If you have consecutive
flashes then you probably have a lean mixture problem or bad mixture problem
or etc. such as bad gas, timing, leaky injectors, vacuum leak, low
compression or maybe more. The flashes tell you if you have spark at the
plug ends.

The O2 sensor causes lean or rich mixture. Unplugging an 02 sensor will
eventually cause rich mixture and raise the idle a bit during idling. Do not
drive more than too long. If it still misses, it's probably the injectors.
Have it cleaned.
Koji

 

distributor cap and rotor!

 

398K? Really?

Jeez...

yes, the O2 sensor, among a multitude of other things, could cause it.
But go back to Basic Auto Mechanics 101 and start there. Make sure
there is no vacuum leak anywhere. That will cause rough running at
idle that disappears at speed. Could be EGR as well. Check that out,
and also, check the injectors.

 

Replaced all the valve cover gaskets. The "ring gaskets" sealing the
plug wells leaked oil into the wells inundating the plugs/ wires. This
helped. Replaced distributor cap and rotor. Cap was cracked at the #3
& #4 electrode. Car idled much better ... but not perfect. Since I've
been contimplating what to do next, we have been driving the car 135
miles daily. The rough idle seems to have "cured itself". (Dirty
injector?). At 5PM Oct 15, southbound US 101 / San Jose Ca. the car
passed the 400,000 mile mark. We took the photo (at 70mph)to go along
with the one taken in Aug of 2001 at 300,000.

Phil

 

Sensor. It could be the sensor. Such as MAP or Idle sensor. I have the
same
problem only during the warming up idle. It's a bit rough idling
during the warming up and it alwasy idle when the RPM is going down
from 2500 to 2000. I can't help it. Usually I have no rough idle on
stop during the driving.
The manual suggests some sensor is not gone bad. I don't know which
sensor
exactly i think the Idle Sensor is not perfect.