Reductant pressure too low
Good Morning, Customer brought the truck to us stating the check engine light is on, and the warning message in the message center in the dash says speed reduced to 5MPH in 60 miles. i tested the DEF injector according to prodemand test instructions (it tested bad) and also found the TSB that refers to the ECM update. We updated the ECM first and the light came back on after 5 miles of driving, so we replaced the DEF injector. We drove it 20 miles and released the vehicle to the customer, he drove it home (around 20 miles) and hooked to his camper, on the way to the campground his wife tells him he needs to stop because something is burning. he stops and went to the back of the truck and he said the DEF smell was so strong that it burned his eyes, and something white was coming out of the exhaust (customer said white smoke but it could have been steam we did not see it).
So now i have the truck back, i tested the DEF injector again, with almost no flow out of the injector and it was dripping out of the end of the injector while i was testing it (it also had white crystallized stuff on the end of the injector). when i took the line off the injector and commanded the pump i had "good" flow. I ordered another injector thinking that one is plugged internally, installed it this morning and drove it 20 miles stopped and let it idle for maybe 15 minutes, got back in it and less than a half mile down the road the lights come back on.
i did not remove the DEF tank and look at the quality of the fluid, however i did get a sample of the DEF out of the pressure line and it looked clear with bubbles (like sprite) is that normal? I'm not very familiar with DEF testing, i did test it with a refractometer and it tested between 32 and 32.5%. is that normal? What am i missing? could i have bad DEF even if it looks good coming out of the line? Thanks in advance!
I have had this with a def exhaust filter that was hollowed out. It was doing a regen and spraying into a hollow chamber. smelled and huge amount of white smoke. That could possibly affect the nozzle on injector?
Does your scan tool show def pressure?
Yes I can, how much pressure should I have? Attached is a screenshot and data file while I was on a test drive. Let me know what or if I need to be watching something else. Thanks!
If any fuel got into the def it can cause this. Easiest way to tell is take the pump out of the bottom of the tank and if it looks like the picture I attached, that's what happened. If so, you replace everything. fill tube, tank. pump, line and injector, even the cap for the filler.
i noticed this morning that there is a white crystallized film inside the tail pipe, I'm pretty sure I've got raw DEF at the end of the exhaust pipe. does that mean i have a bad SCR? or what do i have going on?