Replacement ECM 5.7GXi-C

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RTTGT390
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Replacement ECM 5.7GXi-C

Post by RTTGT390 »

Hi All,

New here, I am looking for a replacement ECM for a 5.7GXi-C V8 2003. Any help and suggestions where to look as my boat was imported to the UK from USA so I have to look for GM Volvo Penta parts.

Many thanks if you can help steer me in the right direction.

Regards

Richard
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Re: Replacement ECM 5.7GXi-C

Post by jhnmdahl »

I'd start here - https://marinepartseurope.com/en/dealer ... %20Control

They say the original ECU 3861772 has been superseded by 3862866. They're out there if you google Volvo Penta plus the part number, but it won't be cheap.
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Re: Replacement ECM 5.7GXi-C

Post by AsLan7 »

.
So glad you found us Richard. I remember seeing one or two pop up on eBay years back, but it will be tough. Keep us posted. And welcome aboard mate!

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Re: Replacement ECM 5.7GXi-C

Post by Titaniumboy »

Perhaps your ECM could be repaired? Maic Salazar Diagnostics has a ton of YouTube videos where he troubleshoots and repairs marine ECM’s. He also has a website with the same name.

Warning: I have not personally had anything repaired by this guy.

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Re: Replacement ECM 5.7GXi-C

Post by RTTGT390 »

I've made enquiries! £2,965.00 Hopefully there is one in stock in England. Thanks for the help.

But I am preferring to rebuild the software if possible.

Thanks.

regards


Richard
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Re: Replacement ECM 5.7GXi-C

Post by Titaniumboy »

I missed the fact that you were in the UK.

I’m not sure what you mean by “rebuild the software”?

Just because I’m curious, how do you know the ECM is bad? What are the symptoms or issues?
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Re: Replacement ECM 5.7GXi-C

Post by RTTGT390 »

Volvo have tried to test the ECM. The boat works fine at low speed. Once you apply load, as in speed the engine shudders and struggles to get speed up. Volvo say one half the ecm is not responding.

My friend is an auto electrician and works on all manners of vehicles including boats and he has the opinion that it is a fuel pressure issue as the fuel pump gets very hot and the engine back fires occasionally. When you keep the fuel pump cool it does not backfire and he thinks the issue lies there.

The other issues is how to reprogram the software. I've been told to find a donor ECM and copy the software from it. Issue is finding one.
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