Posted by Andrew on August 7, 2004, 3:38 am
I have Toyota Echo 2000(90,000 km on it) and was very happy with it
until it started to misfire.
One morning I got off the highway and stopped at traffic light. My car
started to shake like it worked on 3 cylinders. I switched on parking
and it was less. Then after I put on drive and it started to shake
again. When I took off everything was ok. I called my mechanic and
explained everything. I thought it was related to changing donut
gasket which he did one day before(the old one was burned out in one
place and didn't sound good. When he install the new one he pried big
screwdriver against oxygen sensor. I thought he damaged something in
that area). He sad that everything was ok sense CHECK ENGINE light
didn't come on. Then after 3 days it happen again in same situation
(off highway). He suggested to replace spark plugs. I did it on my
own. When I did it I did experiment. I started engine with one coil
off. It did exactly the sama shake and CHECK ENGINE light didn't come
on. Car was not doing any shakes for 10 days and today started in same
situation (off highway). Mechanic doesn't want to run computer check
because light didn't come on. He says that CHECK ENGINE light triggers
computer to make record of problem. He suggested to drive it till it
starts doing that more often or light comes on. What do you think? Is
everything true he says? What should I do? Car runs good and idles
Posted by Andrew on August 8, 2004, 2:06 pm
I understand, that this problem involves spark plugs,coils, injectors,
computer. (Please add more if I'm missing something in my list. May be
I just need to bye injectors cleaner @ Canadian Tire...???
I have replaced all spark plugs by exact the same from diller.
Does anyone know how to check coils, injectors, computer?
I'm sure check would show that everything was ok, because car is
running ok and misfire happens very rare (ones a 10 days).
Or what should I do when it happens again. May be I need to do some
tests while it is shaking, because ones it starts shaking it is doing
that for minutes till I start driving. As far as I understand it is
doing only one cylinder and I need to find which one . Chipper to
replace one coil or injector, then four. Please any advises...
Posted by David Hooey on September 1, 2004, 4:01 pm
Change the plug wires. the higher energy spark in modern cars will wear out
the wire much faster.
The insulation and/or the inner conductor starts to break down. Spark
energy is lost and results in mis-firing.
Posted by Daniel M. Dreifus on September 2, 2004, 12:10 am
email@example.com (Andrew) wrote in message
The mechanic worked on your car.
The very next day a problem arose that had never been there before.
I suspect a high correlation between those two events.
Just because it didn't throw a code doesn't mean there's not a
problem, or that it cannot be isolated and remedied.
But sounds like you need to find a better mechanic and describe what
the first one did so he can focus his initial investigation there.
If by "doughnut" you mean the gasket between the exhaust manifold and
downpipe, and that he pried against the oxygen sensor to loosen the
pipe, that's a logical place to begin.
Oxygen sensors are very sensitive devices, for example, dropping one
can ruin it because there is ceramic material inside that is fragile.
Although it is designed to withstand very high temperature, it can be
If you know he pried against it, you might want to try just replacing
the oxygen sensor first, because the problem is intermittent and may
not appear when testing.