We find out… plus everything else you should know.
Diesels are great. They’re torquey and efficient, and are pushing out some serious grunt these days. They’re also pretty well-behaved these days. But they have a dark side: Their exhaust is loaded up with pretty nasty nitrous oxides and particulates that don’t do the environment (or us) any favours. To fight it, the modern diesel engine is loaded up with lots of different emissions-reduction systems. And one of those is AdBlue.
AdBlue is the new frontier for reducing noxious emissions from your diesel-powered engine. It works in tandem with the usual array of emissions gear (Exhaust Gas Recirculator, Particulate Filter), reducing the amount the harmful emissions that come out of the exhaust pipe of your 4X4.
What is AdBlue?
It’s actually a registered name for a urea-based diesel exhaust fluid, which is also called Selective Catalytic Reduction (SCR). It’s 67.5% distilled water, and 32.5% urea, and it gets sprayed into your exhaust gases. After mixing, it passes through a catalyst, which converts the bad oxides of nitrogen into harmless gases and water vapour.
What happens if I run out?
There are a couple of different scenarios that can occur, neither of which are great news. Most vehicles flat-out refuse to start if they sense they are low on AdBlue; while others go into a low-power limp mode if they sense they are producing too much Nitrous Oxide (Nox). This will either come from the exhaust sensors noticing too much emissions, or the AdBlue tank noticing that it’s empty.
Can I get rid of AdBlue out of my vehicle?
Sure… anything is possible, right? If you want to spend tens of thousands of dollars replacing your exhaust, and retuning your engine while deleting the AdBlue system – go for gold. In other words, it’s not worth the effort and will probably land you in trouble mechanically and legally. If you don’t want the trouble of AdBlue, don’t buy a vehicle with AdBlue in it.
How can I get around no AdBlue in an emergency?
In essence you can’t, really. Modern vehicles are set up to never emit more emissions than the law allows them; so if the car’s exhaust sensors pick up too much emissions, then you’re going to run into problems. Unlike other warnings, you can’t just ignore this one.
AdBlue is urea, which is like urine. Therefore, I can piss in my tank. Right?
Probably not. AdBlue is 32.5% urea and 67.5% water, where the stuff that you wee out is (depending on your diet) 91-96% water and around 2% urea (plus heaps of other stuff). So, AdBlue isn’t just fancy piss – despite your most romantic notions. You can’t really stick your willy in the filler, relieve yourself and call it ‘all good’.
But let’s push this situation to the extreme. You’re stuck in the middle of the desert, and your car won’t start because the AdBlue tank is empty (and you didn’t pack any extra). In this situation, what have you got to lose? Rather than pour water straight into the AdBlue to try and trick the system to get it running, you might as well drink the water, get hydrated, and then pass your waste on to the car. Surely! I asked an expert on the matter.
The Expert: Damion Smy.
Product Communications Manager, Ford Australia.
What happens when an AdBlue-equipped vehicle runs low on AdBlue?
The Everest has an AdBlue status display in the instrument cluster. The cluster will provide a warning, and a warning light, indicating that there is 2,400km of range before AdBlue needs replenishing. Even in the vast continent that is Australia, 2,400km is generally within distance of civilisation. There will be further warnings every 800km before the tank is empty. In the Everest, it’s an 18-litre tank.
What happens when it runs out?
Remember that AdBlue is a consumable; like fuel, brake pads and tyres. If you were to completely ignore the multiple warnings that prevent the tank running dry, the vehicle will keep running. If it’s bone dry, the vehicle won’t start. This is the law: All car makers must engineer this in. The tank is a special polymer that is designed not to rupture, even in off-road conditions that the Everest has been engineered for.
In an emergency situation (like being stuck in the desert) where the vehicle won’t start because of low AdBlue, is there anything (other than filling it) that can get the car running? For example, can you run on limp mode, add water into the system or urinate into the tank?
No, the vehicle will not be able to be started. It’s the same for all AdBlue vehicles; legislation prohibits it to start with no AdBlue in the tank. So, even if we wanted the capability of limp mode or normal driving in this situation, it’s prohibited by law. We wouldn’t recommend water or urine…
What’s better in this situation? Water or urine?
Can’t say we’ve had to test for that… remember that AdBlue is like fuel, you need it to drive. If you have the tank replenished at each scheduled service, you’ll likely never have to touch the AdBlue tank.
So, you own an AdBlue-equipped 4X4. What else do you need to know?
- AdBlue has a shelf life of 12 months. We don’t know what happens if you use stale AdBlue, but it’s still worth knowing that.
- Find out where your AdBlue filler is, and ensure that any mods you have made haven’t impeded the access. Mostly, AdBlue fillers are next to fuel fillers; but sometimes they are tucked away in the boot somewhere.
- Know how to check the AdBlue level on your vehicle, through the multifunction display somewhere.
- Know where to get a top-up. Not all service stations have it, especially if you start getting remote. Dealerships and workshops can stock it, however. Also, it might be cheaper to fill it up yourself instead of having it done at the dealer. Check how much the stealers are charging you per litre of AdBlue, because you can normally get it from the servo for about $1 per litre.
- Keep it in mind when you’re travelling. Know how much you use, and budget accordingly. Typically, AdBlue is used at a rate of about 5% of diesel. But it can vary a bit model to model; how big your AdBlue tank is (compared to your diesel tank) will govern what kind of range you have before refills.
- Get to know the system. Get underneath your vehicle to see where the AdBlue tank is located, and how vulnerable it is to damage. It would seriously suck to puncture it, lose all of your fluid, and have a vehicle that will refuse to start. Also, include it in your trip budget – along with food, fuel and water.
- Find out if you have to manually reset the level of AdBlue, or if the car figures it out by itself.
- Don’t mix the fluids up. Putting AdBlue into your fuel tank is just as bad as adding water; and diesel doesn’t appreciate being put in the AdBlue system. Double check, and keep them separate.