I have a Max party that starts well after a mimuto begin to fail cylinders 2 and 3 the injection signal is cut. Then I stop it and start well but in the minute the same. The ignition is fine because I have a sparkle in the spark plugs.
Surely it is the spark point that is handling the computer, the point is run and the medium cylinders fail, first look at the distributor's lid if it is not spent, if this new one you will have to test it.