79' 318 ecu is live

The confusion was this sentence:
"Even when I grounded the case its still live."

Never use "it" when having used several different nouns previously. Perhaps "it" meant the transistor, which is normally hot, so OK. If "it" meant the body of the ECU case when it was grounded by wire to BATT-, then that is confusing. Either not a good ground connection, or a massive current was flowing.

Not an English teacher, rather an engineer. We try to use exact terms, then English majors fault us for being "wordy and complicated" and suggest ambiguous words like "it" to be concise. I have seen many examples where an English major rewrote something an engineer wrote, then it no longer made sense or was unclear.