Im using an ms3x firmware up to date. The problem is injectors a and b or not firing car has run before. Output a and b are connected to 2 stock s4 550cc injectors. Output c and d still work put they are going through a job perf driver board running 2 low z injectors.

 

Post an MSQ and relevant datalog.

Can you scope the missing outputs? See if there is actually a signal?

Do you get 12V at the injector with the key on?