Full loss of power

[Endoftheroad]

Hi Fuso people..
My 04 Fg649 with 4D34 suddenly lost all power , while still running smoothly. Could hardly crawl up slight grade with peddle matted in 1st.
No engine light.
Walked home, asked mechanic across street "what next?" - told him I had a new filter to go in truck..
He had me disconnect and reconnect my negative battery terminals "to fool computer.."
I did , and drove the 2km to his shop with full power.
We changed fuel filter (which looked clean) and checked the first racor style one which looked clean as well.
I drove away with full power, but after running for ten minutes did same thing approaching my driveway. Almost zero power while still sounding smooth..
Not sure where to go next, nearest dealer/scan gauge is two mountain passes and a four hour drive from my town of 2000 people.
Anything Fuso specific, or diagnostic information to suggest that I could share with my mechanic?
Cheers!

 

[1aquaholic]

You are going into limp mode but surprised you aren't getting a engine light. Do they all come on when you key the ignition? There are two fuses in the fuse panel that if you pull the engine light will flash and you can get the engine trouble codes by the number of flashes. Do a Google search for engine flash codes for your Fuso model. One fuse gives you the code the other clears them.

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[Endoftheroad]

No engine lights, amber or red, they both work now keyed ,and worked before..
Is there a diffence with this truck between a"limp" mode. And what my mechanic is calling a complete "derating"..?
I'll google the flash codes..
Thanks

 

[dlh62c]

Was there an additional aftermarket fuel filter added?

Mitshibishi recommeds not modifying the low pressure side of the fuel system.

 

[Endoftheroad]

Hey dlh62c,
I haven't modified anything, by "raycor" , I meant the drainable filter inline in front of the tank...
Cheers

 

[1aquaholic]

No there are various stages of limp/degrading depending on what the computer identifies is the problem

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[pugslyyy]

When I have had low fuel pressure issues, I get the limp mode / derating. Won't go over 2000 rpm.

It will store a low fuel pressure code that you can read with an OBD2 reader.

Mine is a 2007, so valid for 2005-2007 - so maybe not so helpful for your 2004.

Lately I've been using Diesel Kleen regularly as a lubricity enhancer and the motor seems to like it - I had a low fuel pressure warning the other day, dumped in a bottle of Diesel Kleen and the light went off.

(I'm not here to claim that Diesel Kleen is the "best" additive - but it is one of the more readily available ones, so easy for me to pick up a bottle during my travels).

 

[kerry]

Are you getting full rpm's and low power or not enough rpm's?