Car won't start in morning - Search and Searched

This is not a cold climate issue or MFR problem…


I get in car turn key to “ON” position and check engine light (CEL) comes on for about a minute or so then the fuel pump turns on and check engine light goes out. This is problem is very consistent. I know the light coming on is normal but the time for it to shut off is not.

After CEL goes out I know the car will start and run perfect. If I try to start before CEL goes out it will just crank so I always wait for light to go out.

Car runs and starts great everytime (after light finally goes off).

As the day goes on from normal usage the time for the CEL to go off decreases. For example, if I drive for 5 minutes stop car and restart I have to wait for the CEL to go out before it will start. Later in the day the CEL may turn off quicker (like normal) and the car will start. The problem is at its worst the first start of the day or after car sits for awhile.

I have resoldered the main fuel relay as well as tried another resoldered relay.
replaced the battery, distributor, rotor, plugs, wires, fuel filter.

I checked voltages and grounds at the relay as well as at the ecu. It seems that the ecu (for some reason) is delaying sending the ground signal to the main fuel relay but I don’t know why. When the ground signal is finally sent, the relay activates and the fuel pump turns on and CEL goes off. I am suspecting the ecu but it seems rare that the ecu would go bad from what I have researched. I have also taken the ecu apart and visually inspected for leaky caps or corrosion. It appears ok. Also, I shorted the “blue” connector and there were no error codes displayed from the ecu. Would anybody suspect the ECU at this point? OR could something external causing the ECU not to send the correct signals to the main relay. THANKS FOR ANY INPUT. THIS IS DRIVING ME NUTS…GOTTA KEEP THE TEG GOING…

My guess would be the ECU, you have checked/repaired/replaced just about everything else.

The other possibility, although unlikely, would be the ICU, I have never known one to be intermittent, they work or they do not work.:hmm:94

Update: Car Fixed

ECU was faulty - replaced with used unit.