Hi I just replaced opti (again) and it was running fine. Now car starts bucking and hesitating when it warms up. I got a code 42. I replaced icm and still code 42 also getting a code 16 in stored. I tried resetting pcm and code 16 wont clear but code 42 does. I checked my wiring on the icm and opti harness and the voltage readings are good. Could it be my opti again? The icm harness had 12.4 v on A and B was around 3 volts but when i stopped cranking it I jumped to 7-8 volts ac. C was 0 ohms and d was like 11 volts. Opti harness was 5,5 , 12.4 and 0 ohms. What can be causing this problem? As soon as it starts bucking code 42 pops up. No ses light. Thanks for any help

 

Last time I had a code 42 it was the ignition module