Volvo Penta 5.7 GI-E ECU issue, will only run if one of the senders is unplugged

[nscs]

Volvo Penta 5.7 GI-E. Engine will start and immediatly stop, If I unplug either the Throttle Position, Idle control or MAP sensor it will start and run (although roughly). When plugged into a computer it didn't show any faults, was told it's 'probably' the ECU.
Does anyone know how I can tell for sure prior to buying a new one at great expence?

 

[Thalasso]

Re: Volvo Penta 5.7 GI-E ECU issue, will only run if one of the senders is unplugged

What type of computer/ tester did you use? Automobile testers won't work

 

[nscs]

Re: Volvo Penta 5.7 GI-E ECU issue, will only run if one of the senders is unplugged

What type of computer/ tester did you use? Automobile testers won't work

The mobile boat mechanic had the Volvo Penta software and said that these systems only show limited info and not all faults show up, he rang some one from Volvo Penta and they told him it sounds like the ECU, however I was looking for something a bit more certain before I went out and bought one:blue:

 

[Walt T]

Re: Volvo Penta 5.7 GI-E ECU issue, will only run if one of the senders is unplugged

How handy are you with an ohmmeter and a volt meter? TPS, ICU, and MAP can be checked. I would start with tps, ohm across it on or off the engine, operate the throttle and you should get a smooth change in ohms up one way and down the other. An old style analog ohmmeter is actually best for seeing any disruptions in a smooth transition. ICU and MAP best checked on a running engine, unless you can do a KOEO test. I would be very reluctant to use a tech who cant diagnose a simple tps and wants to throw an ECU at it without knowing the condition of the rest of the system. I'm betting he didn't ring anyone from Volvo. ECUs arent cheap. I suggest finding a guy (or lady) who will take the time to diagnose it and not throw parts at it.