Well, there is actually a very slow drop in the coolant level.
Something like 1 quart per year, and it's been doing this for quite a
while before the misfire appeared. Could all this be a sign of a head
gasket going bad? (I hope not...)
> On Apr 16, 1:40 pm, Tegger <inva...@invalid.inv> wrote:
>> Dan <drn...@hotmail.com> wrote in
>> > 95 Corolla, 4A-FE with 100k miles. When first started in the
>> > morning, after not being driven for 1 day or more, it seems to
>> > misfire (like running on 3 cylinders) for about 10-20 seconds.
>> > After that, the engine smooths out and runs normally.
>> > When the car is in daily use, it starts and runs OK.
>> > What could be the problem?
>> Is the engine using coolant?
> Well, there is actually a very slow drop in the coolant level.
> Something like 1 quart per year, and it's been doing this for quite a
> while before the misfire appeared. Could all this be a sign of a head
> gasket going bad? (I hope not...)
Pull the plugs. With a good flashlight, have a good look at the piston
tops. Are they all the same degree of blackness, and all equally smooth?
If there's one piston top that's noticeably cleaner than the others, you
probably have a head gasket going bad, or corrosion on the mating surfaces
that causes a leak.
OK, thanks, I'll check that.
Is it possible there are other causes to this,
like a leaky or partially clogged injector?
Or maybe some ignition component?
If you want to confirm that the problem is caused a coolant leak. Let
the car set a couple days and then just crank the engine for a couple of
seconds (turn it off right away if it starts). After that check the
spark plugs and see which one is wet with antifreeze.
A pressure test can also be done, but I have seen situations like you
describe where it only seeps a little when the engine is cold and not
at all when it is at operating temp. A quart a year is not much
antifreeze and if it has been doing this for a long time with no change
it may not get much worse and may not be worthwhile to do anything.
> A quart a year is not much antifreeze
I'd personally consider a quart a year to be unacceptably heavy usage. What
drips out the water pump weep hole would be a tiny fraction of that.
Easy for you to say. Your not the one faced with choosing between buying
a gallon of antifreeze and feeding it to the car over the next 8 years
or paying someone to tear the engine apart and fix it.