1991 Deville ECM problem
 

Hi guys. I've had multiple problems for 2 years in the engine department. Missing, starting, you name it. I have been throwing parts at it right and left. Was running bad but at least running until last week. Cranks, sparks and fuel to rail and throttle body but probably not to injectors. Got codes e23,31,53,12,98. Gave up and put in a new dizzy. No change. How to test the ECM or suggest other.


Thanks!


Never mind. After trying to start it a thousand times, the spark plugs got fouled. I reset the dizzy 1 tooth forward and it wanted to fire but the plugs were black and wet. Another new set of plugs fixed everything. I'm guessing the old dizzy was bad as well. It helps not to miss a tooth.