Had Emissions warning for quite some time now. But the adblue was still being used and no major problems.
I had it plugged in last year and it was an intermittent fault.
Never done me any harm but would pop back up within days.
But now its dropping into Power Reducing which isnt good on the Hills.
Diagnosed with Dosing manual. £475 Purchased and fitted. Codes cleared. BUT
Same issue again within 2 days working.
All lines checked and fluid passes through all lines no problem.
All filters changed using genuine parts only. Including the little tiny one on Inlet.
What i will say is since the dosing module has been fitted and I am working the engine hard I can here a ticking noise when under load upto about 6th gear and it stops.
Must be a related noise as I havent noticed it before.
I have searched high and low for advice. Had 3 different people look at it including Daf.
Most searches just bring up the removal companies but I dont fancy that.
So my question is-
Do you need to purge the adblue after fitting a doser? If so how?
And
Any other advice would be great.
You are going to need a Daf tech with Davie to run live data whilst someone drives to see whats going on
No need to purge after replacing dosing module, did they remove and check the adblue injector?
Down pipe off and look into the SCR cat to see if its partially blocked.
Is it the PR engine? only asking as I really rate that lump, excellent apart from oil leaks!
Thanks for the quick reply.
It’s a Paccar Engine. (OIL Leak) Haha. It’s nothing an new seal won’t sort Haha.
The Injector was clear that has been checked by me with an airline and buy a DAF fitter properly.
I will have to get a Tech in with me for a run then
Again. Thank you
As said it will need a DAVIE ,depending on the fault codes it may need a NOX monitor test .Part of is a loaded roadtest on a gradient ,and when all the parameters are met a recording is made and transferred in to a graph ,this graph will show how efficient the catalyst is and if it needs replaced ,the 2nd test is a 5 min static test at 1200rpm this test will test the nox sensors ,again when put in to a graph it will show if either or both are faulty…Prior to the test there are various tests to be carried out on the system …the dealer should have at least 1 person who can carry out a nox monitor test and translate the graphs
The plot has thickened!
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap it 
HandyGrabAndy:
The plot has thickened!
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap it
I would think I must have broken up some debris and that’s when the adblue worked for a few min and now it’s made it’s way to the injector. (Which is a posh word for a pipe with holes in) that’s literally what it is lol
HandyGrabAndy:
The plot has thickened!
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap it
Them little bolts are the devils own work to get out, they either undo no issues or its tiny chisel time, Iirc its an 8mm 6 sided socket when new
The bolt is mild steel screwed into the stainless scr cat housing, not a good mix
Once you have fixed it I would recommend dumping the entire lot of adblue and refilling with fresh
Trickydick:
HandyGrabAndy:
The plot has thickened!
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap itThem little bolts are the devils own work to get out, they either undo no issues or its tiny chisel time, Iirc its an 8mm 6 sided socket when new
The bolt is mild steel screwed into the stainless scr cat housing, not a good mixOnce you have fixed it I would recommend dumping the entire lot of adblue and refilling with fresh
Wow 8mm…
I put a 6mm on it and it never touched the sides.
I can see in the near future a Chisel coming out and hopefully I can get some grips on the old thread to turn it out.
If I can’t manage to get it off and back on using a bolt. What would be the next method of sealing the injector back on?
I won’t be taking the whole unit off just for 1 bolt to be re drilled haha
Plus it may block up again and need to come back off.
Injector off 
Looks like it’s been off before then placed over the nut and the top of the nut had been hammered down to rount it off tight against the injector. No wonder I couldn’t get a spanner on it.
HandyGrabAndy:
Trickydick:
HandyGrabAndy:
The plot has thickened!
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap itThem little bolts are the devils own work to get out, they either undo no issues or its tiny chisel time, Iirc its an 8mm 6 sided socket when new
The bolt is mild steel screwed into the stainless scr cat housing, not a good mixOnce you have fixed it I would recommend dumping the entire lot of adblue and refilling with fresh
Wow 8mm…
I put a 6mm on it and it never touched the sides.
I can see in the near future a Chisel coming out and hopefully I can get some grips on the old thread to turn it out.
If I can’t manage to get it off and back on using a bolt. What would be the next method of sealing the injector back on?
I won’t be taking the whole unit off just for 1 bolt to be re drilled hahaPlus it may block up again and need to come back off.
Im sure it would not be rocket science to somehow secure the injector back in with a couple of large jubilee clips at least when they rust they can be got to easily.
No sealant it just sits in the hole, the dosing modules can also block up, you can strip them down, quite easily, screen wash is good for cleaning out crystalized adblue.
From years of personal experience ,once you get the heat of the rusted bolt off ,I use a mini grinder ,the rest just come out with you fingers once you lift the ad blue nozzle out ,I have never had an issue with the remains as there is a good couple of mm of thread to get a hold off
another small tip that works is a syringe full of hot water ,as long as it is the tip that is blocked,i know you cant see the tip though it won’t take long to see if it has worked or not ,even an airline will clear it if it isn’t that bad
Trickydick:
HandyGrabAndy:
Trickydick:
HandyGrabAndy:
The plot has thickened!
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap itThem little bolts are the devils own work to get out, they either undo no issues or its tiny chisel time, Iirc its an 8mm 6 sided socket when new
The bolt is mild steel screwed into the stainless scr cat housing, not a good mixOnce you have fixed it I would recommend dumping the entire lot of adblue and refilling with fresh
Wow 8mm…
I put a 6mm on it and it never touched the sides.
I can see in the near future a Chisel coming out and hopefully I can get some grips on the old thread to turn it out.
If I can’t manage to get it off and back on using a bolt. What would be the next method of sealing the injector back on?
I won’t be taking the whole unit off just for 1 bolt to be re drilled hahaPlus it may block up again and need to come back off.
Im sure it would not be rocket science to somehow secure the injector back in with a couple of large jubilee clips at least when they rust they can be got to easily.
No sealant it just sits in the hole, the dosing modules can also block up, you can strip them down, quite easily, screen wash is good for cleaning out crystalized adblue.
They changed the dosing valve years ago tricky ,can’t do the strip and clean anymore ,but saying that since they changed it ,the bodies generally rot out before they block up with ad blue…It may be an idea for the op to remove the valve and see if it is rotten ,unless that was the item replaced…To be brutally honest ,no dealer should have problems diagnoising the problem ,the sysytem was out long enough and all the faults are known
norb:
From years of personal experience ,once you get the heat of the rusted bolt off ,I use a mini grinder ,the rest just come out with you fingers once you lift the ad blue nozzle out ,I have never had an issue with the remains as there is a good couple of mm of thread to get a hold offanother small tip that works is a syringe full of hot water ,as long as it is the tip that is blocked,i know you cant see the tip though it won’t take long to see if it has worked or not ,even an airline will clear it if it isn’t that bad
I got it off quite easily to be fair.
I know it’s not expensive to replace but it was Sunday and I had time.
I sat for a good few hours in total with pipe cleaners and even boiled it in a pan for about an hour. Then I get concentrated screen wash from the garage. No luck…
My mate said “is it stainless ?” Yes I replied.
" have a blow torch we can heat it up it will do it no harm" he said.
Walked over the road to his. 5 min later After getting it red hot and forcing the hose pipe down it, it was free. Even heating up whilst forcing water down it. That was the best…
I think I could have sat for another 3 hours easily and got nowhere.
Fit it back on tomorrow
Happy trucker I hope
Yesterday I noticed the power restriction had gone for about 5 min. Then Bang… Back on again.
Got under it again before and its 100% blocked the injector now. Was 100% Clear on Monday.
So my next question.
How does this little thing come off? What looks like a 4mm nut is rusted up.
I assume I may have to snap it
[/quote]
Them little bolts are the devils own work to get out, they either undo no issues or its tiny chisel time, Iirc its an 8mm 6 sided socket when new
The bolt is mild steel screwed into the stainless scr cat housing, not a good mix
Once you have fixed it I would recommend dumping the entire lot of adblue and refilling with fresh
[/quote]
Wow 8mm…
I put a 6mm on it and it never touched the sides.
I can see in the near future a Chisel coming out and hopefully I can get some grips on the old thread to turn it out.
If I can’t manage to get it off and back on using a bolt. What would be the next method of sealing the injector back on?
I won’t be taking the whole unit off just for 1 bolt to be re drilled haha
Plus it may block up again and need to come back off.
[/quote]
Im sure it would not be rocket science to somehow secure the injector back in with a couple of large jubilee clips at least when they rust they can be got to easily.
No sealant it just sits in the hole, the dosing modules can also block up, you can strip them down, quite easily, screen wash is good for cleaning out crystalized adblue.
[/quote]
They changed the dosing valve years ago tricky ,can’t do the strip and clean anymore ,but saying that since they changed it ,the bodies generally rot out before they block up with ad blue…It may be an idea for the op to remove the valve and see if it is rotten ,unless that was the item replaced…To be brutally honest ,no dealer should have problems diagnoising the problem ,the sysytem was out long enough and all the faults are known
[/quote]
It was more about the £500 deposit they wanted and £80+vat per hour to "Diagnose " the issue.
We know the issue was adblue and apart from the main pump and a dosing valve it’s just pipework.
The way I see it my fitter who looks after it is a Scani man and never had Davie software and said its “Intermittent fault” on there laptop. No parts actually show as OS. A friend of a friend who works for DAF come out and I took him for a run. He said both NOX working perfectly and it needs further investigation. £££
The guy who parks next to me said he knows a DAF fitter. Takes it to him. He Gets his Laptop out (Davie) and said “Dosing Valve”
Sounds good to me!
New one fitted all codes off
2 days it’s back in Derate.
I have a look myself and cleared all the lines. The one that looks like and overflow return was a little blocked up. Not fully. Cleaned that out. Forced adblue through the system by airline on the breather pipe for the tank, It flowed well. (Not sure it’s the right thing to do like)
Fits it all back together and goes to work. After working it for about 2 hours it creeped out of limp for about 5 miles but dropped back in within a minute.
Then I could hear the hissing of the injection under load.
Something wasn’t right. Then I inspected the Nozzle (Injector) that was then blocked.
Blar blar… as above.
Money saved and time will tell if it worked.
Plus after searching high and low for something online and finding nothing. People can now see what needs doing and your own time is much cheaper than £80+vat per hour.
I will update again once I have run the truck a little. See how it goes
Im wondering if you are getting adblue but no air to push it down the delivery line, hence the reason its solidifying as its not being blown through?
Trickydick:
Im wondering if you are getting adblue but no air to push it down the delivery line, hence the reason its solidifying as its not being blown through?
My exact thought today when I could still hear the hissing as i was making my way through 3rd - 6th maybe 7th.
Checked all the connections as i had every one off over the last few days.
I got a good 2/3 of a turn on the Air side of the doser. (Foolish me not going over it all)
Limp mode all day again today Haha
Let’s see how tomorow goes. I don’t want to clear any codes unless I have too. I want the Restrictions to remove themselves. That way I know it’s right.
The new doser came with a brass air fitting that’s different to the one permanently attached to the airline so I didn’t use that. But maybe I will if I have to. Just means cutting the pipe. Last resort.
HandyGrabAndy:
Trickydick:
Im wondering if you are getting adblue but no air to push it down the delivery line, hence the reason its solidifying as its not being blown through?My exact thought today when I could still hear the hissing as i was making my way through 3rd - 6th maybe 7th.
Checked all the connections as i had every one off over the last few days.
I got a good 2/3 of a turn on the Air side of the doser. (Foolish me not going over it all)Limp mode all day again today Haha
Let’s see how tomorow goes. I don’t want to clear any codes unless I have too. I want the Restrictions to remove themselves. That way I know it’s right.
The new doser came with a brass air fitting that’s different to the one permanently attached to the airline so I didn’t use that. But maybe I will if I have to. Just means cutting the pipe. Last resort.
Old air fitting on the pipe is just fine, Iirc there are two style of dosing modules and the only real difference is which side the air pipe screws into, I think 8 wheelers and the like had the opposite type to tractor units, some also had heated modules with a cooling pipe running inside the tin cover and if the adblue tank was on the other side of the chassis the pipe run was also heated as was the adblue tank, again all using the engines coolant.
do not cut the air pipe,break off the black plastic seal then remove the metal clips and the nut pulls off then simply push pipe in to the new nut and it will lock in place…If you are not getting air to the main eas unit then there is an air vale on the N/S/F that fails ,possibly why the nozzle is blocking up ,another issue is people who for some unknown reason fill the air filter with ad blue
norb:
do not cut the air pipe,break off the black plastic seal then remove the metal clips and the nut pulls off then simply push pipe in to the new nut and it will lock in place…If you are not getting air to the main eas unit then there is an air vale on the N/S/F that fails ,possibly why the nozzle is blocking up ,another issue is people who for some unknown reason fill the air filter with ad blue
Not seen that one before, used to fill adblue filter wth hot water to flush the LF adblue system out, Iirc was a std LF service item when oil change due.
norb:
do not cut the air pipe,break off the black plastic seal then remove the metal clips and the nut pulls off then simply push pipe in to the new nut and it will lock in place…If you are not getting air to the main eas unit then there is an air vale on the N/S/F that fails ,possibly why the nozzle is blocking up ,another issue is people who for some unknown reason fill the air filter with ad blue
Would this be behind the metal plate 2 bolts holding the plate? NSF wheel arch? I have had an issue there last week too. Leaking 3 way push fit but I am 99% sure that was the Horne.
No leaks there now.
100% getting Adblue and can only describe the noise I am getting as a Pulsing hiss as the fluid 'should’ve be pushing through under load.
It gets fairly loud if I floor it off from stand still.
I can’t find any split in the pipes.
All filters are brand new and the air is definitely not full of adblue hahaha…
Can’t believe people do that
Thanks for the help