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natsys

Seasoned Expediter
Owner/Operator
I will do that.

In the event I need to have it looked at, do you know if it can be driven for a couple or few hundred miles until I can get an appointment? Or is it impossible to say without knowing exactly what the code is?

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Hino123

Expert Expediter
Researching
Its hard to say how many miles. The burner system usually will usually de-rate a 10 bars in the meter. If you can perform a manual re-gen when the bars reach 3, you can buy yourself a little time. Make sure the bars in the meter go to zero. As a general rule a truck will do a re-gen approx every 95 miles. If you cannot perform a manual re-gen, do not wait for the bars to reach 10 before you bring it in. If you wait too long past 10 bars, you can pack the DPR full of soot. Hino recommends to remove and clean a DPR that has more than 8 Grams per liter(G/L) of particulate matter (PM). At ten bars in the meter you have reached 5.2 G/L of PM, a P244B and P2463 will set in the ECU. Keep us posted.
 

natsys

Seasoned Expediter
Owner/Operator
Thanks. That is good direction.

Since it just did a regen Thursday it's sitting at 0 right now so I should be able to get to the work I have scheduled. Normally I keep the dpf on the info screen so I'll pay even more attention to it now.

I did go out and check all the connections of anything I removed or took apart and they're all solid.

I'll let you know what is found.

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natsys

Seasoned Expediter
Owner/Operator
Well, it's been a couple of weeks since the MIL came on so here's what's happened since then:

Nothing.

The light came on Friday after work, so Saturday morning I double checked all the wiring connections and it was all tight. Later Saturday night I really wanted to have a look under the atomizer cover so having done the job already, I knew I could be in there in 20 minutes or so. Within 20 minutes I had the ignitor and exhaust sensor out as well as 3 of the 4 atomizer screws. 3 hours later I still didn't have the last screw out. It was that one you just can't see but have to remove by feel, and the pin-in-head torx bit just slipped--stripped head in the screw. I tried several other types of bits to force it loose, but I only broke or ruined anything I tried to use or alter to fit. So, since it was already dark and I ran out of cuss words I put it all back together and drove it for a few miles--MIL still on. I did notice that plugging in the exhaust sensor, it seemed to click into place but something didn't seem right so I pushed it in a little harder and it moved in a considerable amount more and seated firmly.

Woke up later still stewing about this and remembered that this time I didn't plug the wiring plug into the top of the ignitor. Sunday I got under there and plugged it in, started the truck and still the MIL is on.

Monday I started trying to find someone with DX2 software to have a look at it. A client has a cousin who works at Ryder and takes care of his fleet so I tried to catch up with him, but never could. Probably also going to need the atomizer removed so I can grind off that stripped bolt. Monday leaving work I checked in on the trouble codes and there was no active fault--only an inactive one, but MIL still on. Parked at home, turned the truck off and then on again and still the MIL, but now no codes--active or inactive. Turned off and then on again and the MIL is out.

I wanted to wait for a regen to make sure it was good, and that didn't happen for over a week. Its been a few days since the regen and still no sign of a code or MIL. My guess is that maybe the exhaust sensor plug might not have been fully seated, or is it possible that since the fuel pressure was running on the low side for so long due to the leak that the computer "learned" it to be on the low side and adapted to it, then finding it suddenly higher triggered a fault? I recall some OBD II systems doing that in the past, but I don't remember what sensors they were associated with. It might explain why the guy Hino123 works with has some reseal jobs come back with high pressure readings.

BTW, I ordered some new Torx bits and the "stripped" bolt came right out. My bit must have been worn down and the pin was bottoming out in the bit so that the torx teeth weren't seating all the way down. So, it's all good and I still would do a reseal on my own again if I ever had to.
 
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Hino123

Expert Expediter
Researching
I had some new info pass my way, the tech I work with has had 4 re-seal comebacks all with high fuel pressure faults related to the burner. I made a call up the chain and found that this is not an isolated incident. Apparently when setting the fuel pressure with DX2 (dealer software) it is 5psi less than when it is performing a re-gen. So after a couple days when it actually starts a re-gen the fuel pressure rises over 101 psi and sets a fault. I have been instructed to set it 5 psi lower to negate this issue. The problem is I was unable to get the pressure below 95 psi. Im waiting to hear back, but this could explain your issue. No way to tell for sure without pulling the codes though. Dont beat yourself up too hard. Ill update when/ if i get an update.
 
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natsys

Seasoned Expediter
Owner/Operator
Between this and the "Hino Burner Malfunction" thread it sounds like you're on to something.

Is the fuel pressure regulator available separately? Maybe the new atomizers have regulators that have been updated to correct the fuel pressure issue?

Nice work.
 

natsys

Seasoned Expediter
Owner/Operator
Too bad. It would be nice if the parts were available separately rather than spend so much $$$.

I swear this truck knows when I post. Monday afternoon for no reason the MIL comes on again. The DPF was at 2 bars when parked that day. Tuesday morning it was at 3 on start up. Drove to work which was just barely enough time to warm up but it didn't start a regen on its own--may not have been warm enough, or could be due to the light being on. I parked and did a manual regen, took the usual 15 minutes or so. Afterwards, no codes. After driving a few times during the day the MIL cleared...and then came back.

I know this may NOT be fuel pressure related so until I get it looked at with DX2 this is only conjecture, but if it is then the problem may not agree with what Hino123 was told. The light came on BEFORE a regen, the code was still there when the regen started, but afterwards it was gone. Then later, with no bars and no regen it comes back on. So if this is a high fuel pressure problem it is triggering when the truck is NOT in regen when it should be 5 psi higher.

Just passing this on as any and all info may lead someone to figure out what's going on with this high fuel pressure issue. As a side question, if I should decide to try to adjust the fuel pressure regulator inside the atomizer and see if I can turn the pressure down a bit--without software--how much would be a good amount to back it off? A quarter turn? Half? It probably can't hurt to give it a try and see if it affects my MIL.
 

greasytshirt

Moderator
Staff member
Mechanic
As a side question, if I should decide to try to adjust the fuel pressure regulator inside the atomizer and see if I can turn the pressure down a bit--without software--how much would be a good amount to back it off? A quarter turn? Half? It probably can't hurt to give it a try and see if it affects my MIL.

It's pretty sensitive, I'd say about 1/8-1/4 turn should be sufficient.
 

natsys

Seasoned Expediter
Owner/Operator
Oops. I did it last night so I went 1/2 a turn. Just starting it there was still a fault. Drove a couple of miles and no fault, and a few starts later no MIL.

This truck tends to be fickle so I'll watch it and post if this solved the issue.

GreasyT, when you adjust the pressure is it because it's mostly high, low, or random?

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natsys

Seasoned Expediter
Owner/Operator
Yeah, but at least I have 2 people who can see telling me what to do. That's the next best thing!

Your observation that it's usually high is right on with Hino123's. That at least indicated the pressure needed to be turned down, not up. And if it's correct that there is a point at which it won't lower any more, then as long as the adjustment screw isn't turned too much, it's a pretty good guess that I might be right--even without the software to confirm it.

I'll watch it for a month or so. If there's no MIL, I may be inclined to bump it back up a quarter turn. Or better yet get in touch with my contact who has the software and set it right. Either way, the light is absolutely related to the reseal job and with the information here it has got to be the pressure adjustment.

If I had this to do over, I'd back off that regulator screw a 1/4 turn while I had it out. If it's always high after a reseal, it couldn't hurt. And it's much easier to do when it's in your hand rather than laying on your back holding the regulator with a pair of needle nose vice grips to prevent it from turning.

But as long as the MIL isn't lit, I couldn't be happier!
 

Hino123

Expert Expediter
Researching
I installed a brandy new atomizer on a 2013 with 110k today, after I installed the atomizer I commanded the fuel pump on and monitored fuel pressure.. It was roughly 94 psi, I then commanded a manual re-gen on and recorded fuel pressure. During the re-gen it got to 98 psi at its highest point. That confirms that it does get slightly higher during a re-gen than when commanded on. I will be setting my pressures as close to 90 psi as possible during re-seals from now on. Keep us posted on your MIL and if it comes back on.
 
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