What Happens When the Diesel Exhaust Fluid Tank Runs Dry? We Put the item to the Test
As if the item weren’t tough enough for diesel owners to find a clean place to pump fuel, they face another challenge: keeping their tanks of diesel exhaust fluid (DEF) topped off. What happens if you run the treatment tank dry? We tested to find out, so you won’t have to try the item yourself.
Diesel veterans long ago learned how to handle This specific concern. The following primer can be for diesel-engine newbies along with also gasoline-engine devotees curious about life on the additional side. DEF, also known as AdBlue or Blue DEF, can be an elixir in which’s necessary to make sure in which what exits a diesel vehicle’s tailpipe can be as sweet as an Alpine breeze. Those who turn a DEF ear face harsh penalties.
DEF, available at most service stations for $6 to $10 per gallon, can be a fluid consisting of urea along with also deionized water in a 1:2 solution. the item’s contained in a reservoir separate by the fuel tank along with also can be metered into the engine’s exhaust stream to control certain emissions. Inside the exhaust pipe, the DEF vaporizes along with also decomposes into ammonia along with also carbon dioxide. Those two compounds then react with oxygen along with also detrimental nitrogen oxides inside the vehicle’s selective catalytic reduction (SCR) catalyst. This specific produces three benign tailpipe gases: nitrogen, water vapor, along with also carbon dioxide.
Make sure in which any DEF you purchase can be labeled to comply with ISO (International Organization for Standardization) 22241 specifications. While DEF doesn’t deteriorate over time, the item can freeze, so store your supply in a heated location. The ingredients remain in solution, so no shaking or mixing can be necessary before use.
The Environmental Protection Agency requires makers of brand new light-duty diesels to interrupt the engine’s normal startup routine if the DEF runs out to make sure owners take their clean-air responsibilities seriously. To avoid the problem of owners stranded at the side of the road, every diesel-vehicle maker provides ample warning before the item’s time to add DEF.
The two long-term diesel-powered vehicles currently from the Car along with also Driver test fleet are proving useful for studying DEF consumption scenarios. Here, we’ll focus on the 2016 Land Rover Range Rover HSE Td6 we’ve enjoyed driving more than 30,000 miles since last spring, although we’re also keeping watch over a 2016 Nissan Titan XD powered by a 5.0-liter Cummins V-8.
Our Range Rover can be equipped using a 3.0-liter turbo-diesel V-6 in which sips DEF by a 4.8-gallon tank located under the floor beneath the driver’s seat. in which reservoir’s fill cap can be under the hood atop the left fender. According to the owner’s manual, a full DEF tank should last 6300 miles, although, as everyone knows by today, your mileage will vary.
While there’s no DEF gauge in our Range Rover (some vehicles have those today), the driver can determine how many miles remain before This specific juice runs out by calling up the service menu from the display located between the tachometer along with also speedometer. With the engine off, under the Next Oil Change heading, there’s a notation reading “DEF refill XXX miles.”
We soon discovered in which the earliest warning can be fleeting along with also easy to miss. According to Land Rover, the first message—“Diesel exhaust fluid level low”—occurs at around 1500 miles before the no-restart doomsday. We apparently missed in which message, although at 969 miles before the end, one of our editors on a weekend trip noted: “First DEF warning spotted. There was no orange triangle from the cluster display, along with also an inattentive driver would certainly have missed the item. The warning disappeared before I could photograph the item.”
The next alert appeared 254 miles later. This specific time, there was a bright orange triangle surrounding an explanation point accompanied by the “Fill diesel exhaust fluid tank” message captured from the photo above.
Only 215 miles later, the urgency intensified. In addition to the warning above, a brand new message threatened, “No engine restarts possible in 500 miles.” We continued driving along with also watching without adding one drop of DEF. No additional messages lit up our cluster while we were driving. although during the normal starting routine, the advisory read: “No engine restarts possible soon. Fill diesel exhaust fluid tank. Distance to NO ENGINE RESTART 100 miles.” Again, we added no fluid. although we did pay heed by switching off the Range Rover’s automatic stop/start function along with also by mapping a route close to the Car along with also Driver garage.
After exactly 100 miles, the stern warning “No engine restarts possible” appeared from the driver’s display cluster. We kept the engine running to drive the final eight miles to the comfort of our garage before shutting the item down.
refused us service, as if we’d walked into a 7-Eleven
without shoes or shirt.
To make sure the Range Rover wasn’t kidding, we attempted to fire its engine although found no sign of life under the hood. As we had been warned, without DEF our diesel refused us service, as if we’d walked into a 7-Eleven without shoes or shirt. We promptly began resuscitation procedures. Adding 2.5 gallons of DEF did not—to our surprise—revive the patient. The engine would certainly not start until we tipped in another 2.3 gallons of juice, filling the DEF tank to its brim. Then This specific diesel commenced without hesitation, idled nicely, along with also ran perfectly throughout its next journey—a 250-mile jaunt to Chicago.
While the frequency of warnings does vary, all modern diesels give their owners plenty of notice in which their DEF must be replenished well before the dry-tank doomsday occurs. Our Titan, for example, includes a gauge in which’s handy for checking the DEF level before embarking on a major trip.
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- Long-Term Road Test Update: Nissan Titan XD
- Land Rover Range Rover Tests, Reviews, Specs, Pricing, along with also More
This specific experiment convinced us in which keeping track of your DEF can be no more difficult than monitoring the engine’s oil level. There are ample warnings, along with also the Range Rover’s supply tank can be large enough to last most drivers several months. Considering how effective This specific strategy can be for cleansing the exhaust, the half-cent per mile we spent in This specific test for DEF can be quite reasonable.