Day one with motors back in boat. Started on water hose ran good, no codes. Put in water and started at dock coded (Idle map STR) problem is I don't think my set up has map sencors. It does have 2 IAC's on each motor. I've swapped them form motor to motor with no change. Motor will run but shacks at idle, when you put it in gear it will run but will not recover from the drop in RPM's and cuts off with in 20-30 sec. I've done all I can think of, any ideas will help.

Thanks
Dwayne

What ECU are you running ?

Mercruiser 555 ECM, they have been retuned for my motors. They ran pretty good last year but broke a valve spring. I then found some stuff wrong with the set up on the heads. This weather I pulled both motors had them checked out and redid the heads with top dollar parts. Reinstalled in boat and starboard motor isn't happy.

The beauty of having 2 motors is you can swap parts between motors, one at a time (ecu etc) till you find the culprit.

Are these whipples ?? Im pretty sure whipple uses a two bar map sensor, I found this on another thread


Idle Map STR means idle RPM MAP strategy in which is the same meaning as MAP idle check in which means Sensor rationality loss of vacuum check.

Clear the codes, refire and see what comes back