So i just picked up a scan tool which is OBD1 compatible. It came with the OBD 1 connector. For some reason its not seeing/reading a connection. i have all but ohmed each wire on the tester out. i am trying to figure why my CEL illuminates during steady state driving. if i shut the car off and turn it back on the light wont illuminate again for some time. i am thinking its the o2 sensor (but which one).
questions...i am pretty sure the 94 is OBD1 with the OBD1 connector. correct? i am the original owner and never read the computer.

thanks

 

I have a 95 3.4L and its an OBD "1.5", OBD1 Computer with an OBD2 connector. The OBD2 connector is different than the OBD1 connector. about the only time I have heard of them not talking is when the PCM is dead. I believe if they die they run in open loop.

 

This is almost dead on. I would add that with the 4th Gen the 94 is the only OBD1 year. 1993 does not follow the OBD standards. 1993 is more like say 1988 camaro then a 1994.

Also there is a communication side of the PCM, It can fail and have no effect on how the car runs but the PCM might as well be a brick when it comes to talking to it. There are also a data line that are very sensitive even the slightest bad connection and the PCM will not see the "wake up" call from a scanner. Without the wake up call you are back to a brick.

 

Well looks like i should have read the manual. The actron manuals states i need to hook up a 12 volt source. I figured that the batteries for the scanner screen would have been sufficient. Thanks for the help.