2010 Hino 258 p0087

Niko · Aug 9, 2017

I have DX II software. How would I find it using that? And thanks for all your help guys.

Hino123 · Aug 9, 2017

Monitor the injectors and look at the balance rates when the truck is up to operating temp (176 degrees or so) New injectors should be roughly +/- 3mm. If you see a number near 20 it could indicate a restriction in the rail on that cylinder. Numbers over 5 and thats usually when I start to recommend injector replacement. Can you monitor the balance rates and post results here? Be sure to note wether it is a + or - number.

Niko · Aug 16, 2017

If you could give me the torque specs that would be great. Just pulled apart the common rail. Took dampers out. Didn't see any spring remninents but did have 2 that looked clogged.

Hino123 said:
There may be debris lodged in the common rail. I have seen multiple times, inj pumps come apart and lodge debris in the flow dampers. Removing and cleaning the rail could be done by an amature in under 2 hours. There are no parts involved just a little labor. Injectors however, are expensive and take 4-5 hours depending.
I would suggest the following. Start the truck and using two fingers pinch the fuel lines from the common rail to the injectors. You should feel a pronounced "pulse" of fuel. If you have one or two lines that have no pulse, or feel weak compared to the others, you may have debris lodged in the rail. I would then COMPLETLEY disassemble the rail and flow dampers and re-install. ( be careful not to loose the copper washer behind the pressure relief valve on the far lh of the rail)
If all feel like they are pulsing a good shot of fuel, then you likley have failing injectors. You may have both. New injectors will not fix a debris in the rail.
If it was me id clean the rail anyway and see if it got better. Its essentially free and its not going to hurt it. The whole fuel system needs to be inspected in this one I think to find your root cause. If you need torque specs or any info id be hlad to help.

Niko · Aug 17, 2017

Good morning gentlemen. I took the rail out, cleaned lines and dampers. I didn't see that much fuel coming into the rail from the main feed line. I'm kind of concerned. Maybe a restriction somewhere between the supply pump and rail? I changed the line from the filter into the back of the pump. Any ideas?

Hino123 · Aug 17, 2017

Will this truck make it to Tampa? You have dx2 software, you can monitor actual and desired fuel pressure. They should mirror eachother closley through all rpm ranges. I would look closely to see if actual and desired fuel pressure match. Warm up the truck(176 degrees). Set the dx2 to record actual and desired fuel rail pressure. Powerbrake it in the yard a few times then take it out and beat on it. Then at the bottom of the screen, (you maybhave to move the little retangular box over) there is a hyperlink that says display changeover. Click this... this will lay your actual/desired pressures that you have just graphed on top of each other. They should be pretty damn close. If they are not close I would suspect a fuel inlet restriction. Pm me your phone number. It shouldnt be this hard if you have the software.