Cummins 4BT & Diesel Conversions Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1 (Edited)
I have a question for any diesel mechanics out there.

My truck is a 2000 Mitsubishi FG and it has a 3.9 liter Mitsubishi Fuso 4D34 engine.

Lately it's been a bit low on power so I took out the injectors and sent them to be cleaned and set up.

When I got them back he told me the spray patterns were a bit wonky and not spraying all that well, plus some of the pressure values were set at 180-210 bar.
The setting calls for 230 bar so he set them there. I have the full manual here

Anyway I reinstalled them and have been driving for a few hours. Now, the truck has much less power. What's with that?
All filters are new BTW.
It seems to rev ok but has no power like before. And it was pretty gutless before.

He pulled them again and rechecked them all but he said they are as good as new. So I'm stumped.

I pulled them to get more power. Now I have even less. What can I do?



Steve
 

·
Registered
Joined
·
9 Posts
Discussion Starter #6
I replaced the water temp control unit on the engine, since I got a code to do so.
No changes.

I think since the engine was ok (but just a little weak) before we took out the injectors reset the pressure and cleaned them, the engine then was gutless after we reinstalled them, I even took them back out and sent them off to set back lower like they were, but no change so I took them out again and sent them off to set the stupid things to spec one last time.

Anyway my thinking is the computer has changed something and is now in "limp mode" that's just what it feels like. So I think the computer needs to be reset.
only a dealer can do that I think.
I really wish I could bypass all the computer crap and have a decent power engine like I know this would be.

Unplugged the battery to see if it would change anything but no change.
I have now spent $650 and about a full day screwing around with this junk I'm very frustrated and out of ideas.
Sending it to a shop to test the pump output is a good idea, I guess that's more money but I'll do that next.
But I still think the computer is telling it to put out less.
The dealer is 1/2 a day and a ferry ride away just to drop if off. Plus a follow car to bring me back. Then do it all over again when it's ready to be picked up.
 

·
Registered
Joined
·
5 Posts
I replaced the water temp control unit on the engine, since I got a code to do so.
No changes.

I think since the engine was ok (but just a little weak) before we took out the injectors reset the pressure and cleaned them, the engine then was gutless after we reinstalled them, I even took them back out and sent them off to set back lower like they were, but no change so I took them out again and sent them off to set the stupid things to spec one last time.

Anyway my thinking is the computer has changed something and is now in "limp mode" that's just what it feels like. So I think the computer needs to be reset.
only a dealer can do that I think.
I really wish I could bypass all the computer crap and have a decent power engine like I know this would be.

Unplugged the battery to see if it would change anything but no change.
I have now spent $650 and about a full day screwing around with this junk I'm very frustrated and out of ideas.
Sending it to a shop to test the pump output is a good idea, I guess that's more money but I'll do that next.
But I still think the computer is telling it to put out less.
The dealer is 1/2 a day and a ferry ride away just to drop if off. Plus a follow car to bring me back. Then do it all over again when it's ready to be picked up.
You need to crank up the Injection Pump to compensate the "new" injectors. Both injectors and injector pump wore out whit the use at the same rate if you fix one without touching the other this is what happens.
 
1 - 7 of 7 Posts
Top