Knock Sensor Installed but now more trouble

I recently had a knock sensor installed after my 94 SW2 with 100K
miles on the motor/trans indicated the knock sensor was bad via the
code reader and the symptoms were high rpm's and low power and check
engine light on. I have had this new knock sensor installed and had no
more trouble for 1 week but yesterday on the freeway the rpm's shot up
to 4K higher than before and the speed dropped from 75 to 60 mph and
then the temperature doubled and the check engine light went on. I
immediately turned on the heater to cool the engine down and limped
all the way to my mechanic. The mechanic had trouble with his computer
and removed the code on my car. Any ideas as to my trouble and which
is a good code reader for a 94 Saturn SW2 that I can purchase? Is it
possible when my mechanic installed the knock sensor he needed to do
something else after installation or is this a whole new problem?

Thanks Linda

 

On a '94, you shouldn't need a code reader. It is an OBD1 system.
There is a proceedure at the reader plug by jumping two terminals and
read the flashing check engine light. I don't recall the terminals to
jump at this time. You will get 3 flash series of 12, then the
flashing codes. Once code 12 flashes again, you have them all.

A code 12 will be 1 flash, short pause, then 2 flashes. After 3 series
of 12s, the actual codes will appear with the same method.

James

 

I am not aware of anything more you need to do after installing a new
knock sensor.

Clearing all codes is recommended after a repair but will not cause
problems. Be sure to have someone check your battery condtion and
charging system. A battery going bad can cause all kinds of strange
things to electronic sytems.

James

 

James,
One more thing on the 94 twin cam is there a carborator of fuel
injection? I have a Haynes shop manual but it doesn' seem to indicate
some had carbs.
Lin

 

They never had carbs

 

If you insist on a Code Reader for your Saturn, I would suggest this
one:

http://www.amazon.com/Actron-CP9001...45?ie=UTF8&s=automotive&qid=1178656898&sr=8-2

All fuel injection.

James