I actually have a few 338 Hino trucks, they are all 2015 or newer, they are all garbage packers. Most of them have been fairly reliable in the emissions department. I have 2 in particular that asks for a stopped regen at least once sometimes twice a day, they don't seem to be doing auto regens like my other Hinos, you can do the manual regens without any problems, when I plug in and do a forced regen the temps and other parameters seem to be fine, one of the problem trucks has 130,000 miles the other has about 80,000 miles
Hino 338 will not automatic regen
- Thread starter dsan6t5
- Start date
The truck with 80,000 miles went out today, first thing this morning it was asking for a manual regen,7:30 am, the driver hit the button, let it go, regen ended after about 20 minutes, the bars were back down to zero, by noon it was up to 5 bars and asking for a regen again
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What scan tool are you using?
With DXII, you can go into engine customization and change the soot amount. Change it to something like 2.3 and it'll put the DPR graph to three bars, which is when it will attempt an automatic regen. Then you can look at temps and stuff during a driving regen, which sounds like when the problem is occurring. Sounds like it's not getting hot enough.
As far as regen frequency is concerned, if it's regenerating correctly, the graph will take about 100 miles to go from 0 to 3 bars and then auto regen. With the low speed and duty cycle of a garbage truck this frequency will probably be different.
The aftertreatment injector may be at fault. If the injector wasn't getting correct fuel pressure it would set a code. Sometimes the injector housing gets caked with soot and that can interfere with the spray pattern. Removing the housing means draining ALL the coolant out of it. Use the block drain on the front of the oil cooler.
If your tool gives you access, find the DPR inlet and outlet temps saved in System Protection Data.
With DXII, you can go into engine customization and change the soot amount. Change it to something like 2.3 and it'll put the DPR graph to three bars, which is when it will attempt an automatic regen. Then you can look at temps and stuff during a driving regen, which sounds like when the problem is occurring. Sounds like it's not getting hot enough.
As far as regen frequency is concerned, if it's regenerating correctly, the graph will take about 100 miles to go from 0 to 3 bars and then auto regen. With the low speed and duty cycle of a garbage truck this frequency will probably be different.
The aftertreatment injector may be at fault. If the injector wasn't getting correct fuel pressure it would set a code. Sometimes the injector housing gets caked with soot and that can interfere with the spray pattern. Removing the housing means draining ALL the coolant out of it. Use the block drain on the front of the oil cooler.
If your tool gives you access, find the DPR inlet and outlet temps saved in System Protection Data.
Well after a bunch of help and information from Greasytshirt I was able to cure the Hino’s issue of way to frequent Regens, it turns out that the auto Regens were not getting hot enough, the truck would get up to 3 bars on the gauge and go into auto mode, the problem is that the auto Regen was not burning any of the soot out of the system, it would go from 3 bars (then Auto Regen) right to 4 bars then onto 5 asking for a manual Regen, after you pushed the button and gave it a manual it would drop down to 1 or 2 bars, run fine for a couple of hours and then do it all over again. Plugged in Hino DXII and changed the soot pile up level to the point of 3 bars to make it auto Regen, then drove the truck down the road monitoring the temps, the Regen was getting max 700 to 800 degrees input and output temps, not hot enough to do any real cleaning! Greasy suggested either a bad 7th injector or a plugged DOC face, we had just had the Filter and DOC baked out and cleaned about a month or so ago so I opted for changing out the 7th injector, that was the fix! The truck went out on a test drive and the auto Regen was over 1000 degrees, it dropped the bar gauge right down to zero after a short driving Regen. The truck has been out doing routes for the last couple of days trouble free
Awesome. 2015-later trucks have far fewer regen problems, thankfully this one was easy to sort out.
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