I have an s10 with a 4cyl 2.2l engine. I Got off work and was cold so I revved the engine and it started shaking and I lost alot of power. I changed plugs and wires and all the things for a misfire. Then found out the code wasnt misfire it was 0200 fuel injection circuit malfunction. So I started by getting a noid light. Injectors 1 and 2 were good, 3 didnt come on at all, and 4 stayed on but got brighter rhythmically. So I checked the wires from fuel injector connectors to the pcm for resistance and they were good.I checked for voltage in the injector connectors with key on engine off and didn't get any voltage. But I did check it for ground and it was present. Someone said something about my power and ground at my pcm but wasnt sure how to test them two. Electricaljust isnt my strong suit. I appreciate the help.