1994 Accord - sticky valves?

1994 - 4 cylinder Honda Accord - 310K

My wife uses this car for short open road trips (6 miles) to and from work
each day. She has not been warming the car up enough in the recent cold PA
winter mornings, and it had been awhile since I changed the oil (3800
miles).
There is a rough idle that I assume has something to do with something
sticking;
valves, lifters? While driving, this rough idle turns into a slightly
perceptible
vibration. I have noticed these symptoms in the last 800 miles, and I think
they
are oil related.

I just changed the oil. If these symptoms persist, should I add an additive
to the
oil, or given the high mileage (310K), would a gentler approach be to change
the
oil in 1000 miles? Obviously, the car owes me nothing.

Gary

 

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

You need to take the car for longer runs and it sounds like an injector
(or all of them) is gunked up. Throw a can of Techron in the gas tank
and find an excuse to go for a long drive. _DON'T warm up the car on the
driveway_.

Install a block heater if you want heat. Read the owner's manual.
https://techinfo.honda.com/rjanisis/RJAAI001_OMANUAL.asp

When the engine is warm, rev the snot out of it.

'Curly'

 

How's the oil consumption?

Other than Curly's Techron suggestion...

Warm the car up, then take it for an "Italian Tuneup".

Drive it like heck for a few miles: Full throttle acceleration, let the
engine bounce off the tranny's upshift limits, that sort of thing.

I think you'll be surprised how much that smooths the idle.

If this does not work, you may want to get a compression check done. Such
vibration at high mileage can mean one cylinder has excessive variation
from the others.

 

and speaking about oil consumption, just a little oil on a spark plug
goes a long way towards a vibration...

I did this a while back with my mother's car.
Left quite the cloud of black smoke when it downshifted and approached
redline.
Ran fine after that.

 

I took everyone's advice. I added some Techron to the gas and after it
warmed up I "ran the snot out of it". The rough idle is gone and it sounds
as good as it ever did with 300K miles. The oil consumption is very good. I
seldom need to add oil between oil changes (3000 miles).

Do I understand correctly that it is not good practice to warm up cars on
cold mornings? I may have read that awhile back on this newsgroup.

Thanks,

Gary

 

In the Old Days you had to let the engine warm up to the point where it
would run at all when asked to take a load. We're talking 1930s here. These
days all you need to do on a cold startup is to let the idle stabilize and
allow the oil to distribute itself. This takes no more than 30 seconds.

After that you just drive it gently until the temperature gauge shows full-
hot. Wait five minutes or so longer to allow the oil to warm up too, then
let 'er rip.

An Italian Tuneup once a month or so will help keep the roughies away.
Really.

 

Thaks. It makes sense now. My wife's driving to work is just the
opposite of an Italian Tuneup.

Gary

 

i've always thought that Hondas are somewhat unsuitable for city
driving. Honda engines are designed to run best at full throttle and
at red line Had i not learned about Honda R&D in racing engines, i
would have thought that they designed by German engineers with no-
speed-limit autobahns in mind.

the "Italian tune-up" works for me too. My trip to work is short and
every once in a while i take my Honda to the alternate route, go to
the freeway and run with wide open throttle, and watch her shifts at
red line. Heck, she runs a lot smoother at 95 mph than she does 45

On the other hand, my Honda also does well when stuck in a traffic
jam, crawling with the engine at idle for hours and still remains
cool, while other folks profusely pull over cause their engine
compartments are having a steam bath party.. haha

Cheers!!!