93 Honda Civic DX Vibrates/Stumbles on Accel.

Hello everyone,

After numerous hours of searching on google groups, I believe I have a
better understanding on my car. My car has 127K, bought it with 118.

I bought the car this past August and here is what I have done to it.
* Fuel filter
* oil change every 3K
* replaced both front hub bearings
* New plugs, cap, plug wires.
* Transmission Flush
*** The last three were done in the last month.

Now for the problems.

1. After the car has sat overnight (8-9 hours) and I come out to start
the car. I put the key in and the fuel pump comes on and then goes off
like normal. I turn the car over and the car will continue cranking for
about 5 to 6 seconds without starting, and if it does start, its very
rough like its struggling for something, then finally runs and idles.

* When cold say 10F to 30F I may have
crank the engine 2 or 3 times

before it starts.

Now here is what I do normaly now that the temps are starting to rise
in the morning.
I will turn the car over for about 5-6 seconds, then stop, then turn it
over again and it starts right up. Any ideas here? I also get the smack
sounds that hondas are known for when cold.

* After the car is started, mostly when
cold. The engine idles rough like its going to quit, then I
give it some gas. It will idle rough like this for a good min or 2.
However after driven for say 5 min. I will turn off the car, and it
will start right up again when I turn it over again, and the rough
idle is gone. Any ideas?


2. The next problem is vibration ONLY when I depress the accelerator.
In the morning though while the engine is still cold while im driving
around there will be no vibration.
* The vibration is right under 30mph. If
i go past it or under it its fine.

Now accelerating onto the highway, The acceleration is rough, and once
I get up to 55-65mph while depressing the accelerator slightly here and
there to maintain speed, there is vibration. As I accelerate to about
70mph, the vibration subsides a small amount. Past 70 mph the vibration
slowly comes back.

* The engine is at normal temp by now,
and it seems that once at this
temperature, is when the vibration
starts.
* Most important!! When the car is at
normal temp. the vibration is felt
from just under 30mph to 70mph.

Note, anytime I let off the accelerator and at any speed, the vibration
will go away.
Also I have a thinning rotor on the left front, could this be causing
any of this?
The dealer that sold me the car, said that the timing belt was changed
at 94K, though I have not found record of it.

Lastly I have had this car for about 6 months now and and these
symptoms have been the same, not getting worse, and maybe a bit better
with the tune up. I wanted to make sure I have all the details in here.

Thanks everyone

Kevin.

 

I'm no a Honda expert, but it sounds like either your idle air system
(which I won't discuss; I work on VW) or your O2 sensor (assuming you
have one). I would disconnect the sensor and see how your car
runs--assuming Hondas will run in a safety mode, idle and startup
should be smooth. If not, perhaps a temperature switch? In fact,
disregard this post and wait for a Honda expert. ;-).

 

p.s., the vibration could be caused by anything related to the
alignment (tie rod ends, etc.) or a bad tire--jack it up and look for
flatspots or uneven wear patterns.

 

starting problem may be a leaky injector - run some cleaner through it.
will probably help the acceleration issue too.

stumbling problem sounds like ignition. make sure the ignition
components are CLEAN and in good order. consider a very light coating
of electrical silicone grease inside the distributor cap.

 

Thank you for replying. One thing that has really gone downhill is my
mpg. When I got the car in the summer I was getting 350 miles on a full
tank. In the past two months I have slowly declined, and now im lucky
if I make it to 250 on a full tank. I do mostly highway driving, that
shouldnt make it worse?

Thank you everyone

Kevin

 

where do you live? have you noticed the problem in the past?

reason im asking, is some states mandate "reformulated fuel" for the
winter months. RF gives lower mileage, but less smog.

why smog is more important from nov-mar, rather than say in the middle
of hot-n-smoggy july is beyond me.

 

I see you did some maintenance on this car. I hope you used genuine Honda
parts (not aftermarket ones), for the plugs, cap, and wires. Because they
will make a difference, particularly in ensuring your ignition coil and
igniter last a long time.

Getting back to your symptoms: Make sure you also have a new air filter. I
also lean towards the oxygen sensor being bad on your car. Otherwise, here's
a comprehensive list of items to do, all of which you should strongly
consider doing, especially for a car this old, with an unknown past history:

http://home.earthlink.net/~honda.lioness/id11.html

All the items listed at the site above are due every few years anyway, so
it's not like you're throwing money away. What you're doing is /investing/
this money, with the added bonus that this tuneup may very well fix the
engine stumbling problems.

You could have overlapping problems, so, say, adjusting the ignition timing
and topping off and purging the cooling system of air are necessary for a
full fix.

Your car's old but the miles on it are not bad. You should get several more
years out of this car, assuming it hasn't been maintained too badly in the
past.

On my list at the site above, you could start from cheapest to more
expensive to replace/maintain/check on your car, checking whether there is
improvement after each change. The last (= most expensive, but easy) item to
do would be the oxygen sensor.

https://www.automedicsupply.com/ has fantastic prices on genuine Honda ( =
OEM) oxygen sensors compared to your local dealer or other Honda online
parts sites. $75 or so, tops, for a new sensor for your Honda. Autozone will
loan you an oxygen sensor wrench, no charge.

Updates welcome.

 

P.S.
www.autozone.com has a free online repair manual for the 93 Civic. It gives
the steps for a proper purge of air from the cooling system, for example. It
may take 30 minutes or more for the cooling fan to come on twice during this
procedure, so be patient. Ask if you can't find something at the autozone
repair manual site.

Also, you mentioned a "thinning [brake] rotor" earlier. Do the symptoms you
gave earlier occur regardless of whether you are braking or not? (They sound
like they do.) If so, I'd eliminate the rotor for now, and assume, for now,
it's an engine-related problem.