Does the check engine light go on and
off intermittently? The o2 sensor may
be ok But you could have a broken
exhaust in between the motor and
catalytic converter where there is a
flex pipe. this will break due to a
broken motor mount. you will notice
the car getting louder then usual
possibly. This may cause your check
engine light to come on for a long time
and then go out all the sudden for a
long time. you went to the parts store
or mechanic and they said the
computer reads an o2 sensor going
bad. I have a 97 that is doing this. if
the exhaust is broken it can cause the
o2 sensor to get confused possibly and
the check engine light will come on if it
thinks you have a bad o2 sensor. also I
need new control arms on mine. this is
a steering part. it in jerk when it ships
to about 2nd or 3rd gear especially
while going around as sharp left curb.
I keep having to get a front end
alignment. also a thumping sound
occurs when taking off and applying
brakes. it could be that you have those
two problems at once. have both of
those checked out. also have a
mechanic check the fuel pressure with
a gauge. A fuel pump failure is very
likely in this particular car. i have
heard of cavaliers 97-99 with a bad
fuel pump. when you get the motor
mount fixed, if this problem exists,
keep an eye on how good your
transmission is doing especially if the
motor mount may have been broken
for a long time. these are all common
problems with 96-99 cavalier or
sunfire.
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