Injection pump problems on 99 FG. Anyone swap in a mechanical pump?

kerry

Expedition Leader
Started having IP problems in our 99FG last April. Initially hard to start and no rev above 1800 rpm's but then quickly progressing to no start. Having no good place to work on it I took it to our local (former) Fuso dealer and it's been in their shop since April (it's now almost December). They've swapped in three rebuilt IP's and 2 ECM's and it's still not running right. (they also replaced all the injectors). I think they're at their wits end. They've actually had the Mitsubishi truck rep on site to help them try to figure it out. Then today, in the process of researching the purchase of a camper in the UK, I discovered that on 1990's Ford Transit diesel, people are swapping in a mechanical pump once the original electronic pump starts having problems. (Their EPIC pumps similar to the 99 FG pump I think). Has anyone done this or considered it. I'm pretty sure the 4d34t had a mechanical IP at some point in time prior to 1999. It would necessitate the swap to a mechanical accelerator pedal but I'm not sure what else. I know some people have had similar problems to mine with the electronic IP and it seems like it's frequently very difficult to diagnose. Having a mechanical pump would definitely simplify things.
 
I'm planning on doing this swap myself. Got the mechanical injection pump, simpler ECU, gas pedal assembly and the ECU conversion mapped out. Figured I'll start tackling this if the current injection pump or ECU starts giving me grief.

I'm using this thread as a source -> https://forum.ih8mud.com/threads/mitsubishi-4d34-2at3b-diesel-swap-into-96-fzj80.489409/page-15. He starts talking about his conversion on page 15 with pictures.

As for your current issue, it does remind me of my experience with my land rover discovery and the shop I usually go to. All these guys work on are land rovers, so they know those machines in and out. They spent a month troubleshooting why one cylinder was running cold. Swapped ECU and all that. I asked them to let me take it home so I can troubleshoot it myself.

Turns out the spark plug wires were swapped between two cylinders.

And that's fine. I troubleshoot complex systems for a living and it's amazing how the strangest symptoms can be caused by just the simplest things. Especially electrical. Sometimes when we're in the thick of it, we forget to step back and first work through the basics.

So all that to say, if they've swapped 2 ECUs and 3 injection pumps into it, well clearly it's not that. And you've already confirmed fuel delivery is unimpeded. So it has to be something simpler.

Since you're dealing with a computer, it'll be sensitive to some usual culprits. Could be that one of the grounds got corrosive. I'd first start by confirming each one. Could also be a short or a cut in the harness somewhere. It's a gigantic PITA but I would grab a multi-meter and confirm continuity from every single wire that goes to that injection pump, engine, sensors, etc. all the way back to the ECU connector.

Or god forbid it could be as simple as a low battery.
 
Something I forgot to mention in our previous discussions...
I'm remembering that in those earlier models there is a small strainer in the fuel line, in one of the banjo fittings I believe.
This filter has been know to get blocked, which restricts the fuel flow getting to the injector pump, which has the effect of starving the engine of fuel at higher RPMs.
Has that been checked?
 

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