Diagnostic Port Location(?)-2003 Carver 396

[Bootlegger137]

I am having issues with my Port engine on my 396. The engine (once started) runs rough at idle, oscillating between 700 and 1000 (Approx) RPMs, Sometimes it will level out for a bit, only to start oscillating again. Once on the water, the engine will not reach 3000; which means my SLOW circuit is activated. I decided to buy diagnostic software from Diacom, along with a few nifty plugs to plug into the EEC to read the codes.

The only problem is, I can't seem to find where this diagnostic port is on my Volvo Penta 8.1 Gi Engine. Does anyone happen to know where it is?

[bud37]

Is the rinda/diacom adaptor round , how many pins ? Usually/may be close to the ecu, it may be tie wrapped away/hidden if it has never been used.

[Bootlegger137]

The plugs are both rectangular IAW the specs from the Diacom website. I have been looking all over the engine-attempting to trace the wires coming out of the EEC to a downstream location. I am not sure why this should be so hard.

[Bootlegger137]

And the EEC:

[bud37]

Yup those look like what I had.....different engine but there was a dead ended plug with a cap to keep it clean.......took me a while to find as they were pushed down under the harness........just get a bright light and go slow you will find the data port......sorry I don't know the exact location for that engine.

[Bootlegger137]

I found it. It was located under the fuse box; after removing a cover, there it was.

[buster53]

A couple of issues come to mind that could cause your problems, all fuel related.
Bad gas, water and/or trash in the tank, fuel filter(s) clogging up (each engine may have 2) anti-siphon valve needs replacing, fuel injectors getting clogged with trash.

[Viper]

QR_BBPOST.....the engine will not reach 3000; which means my SLOW circuit is activated......

Not necessarily. Usually if that's the case, there will be an engine alarm going off at a regular interval to indicate that. Are you getting a regular beep?