What to Do When the Urea Nozzle is Clogged?

[OAlice]

The solutions for a clogged urea nozzle are: 1. Use a small ultrasonic cleaner for cleaning; 2. Soak in hot water with the spray end immersed in the liquid. The reasons for a clogged urea nozzle are: 1. The quality of the vehicle urea solution does not meet the standard; 2. After the engine ignition is turned off, the residual urea solution in the nozzle pipeline crystallizes, causing blockages in the pipeline and nozzle; 3. The urea nozzle is located in the exhaust pipe and is exposed to high temperatures for a long time. When it does not receive the cooling effect of the urea solution, the urea nozzle gets damaged; 4. If the SCR system is inactive for a long time, the residual vehicle urea solution in the SCR system crystallizes and blocks the pipeline and nozzle; 5. Complex physical and chemical reactions occur in the SCR system, forming deposits that accumulate over time, leading to nozzle clogging.

[MacFrancisco]

I'm relatively new to diesel vehicles, and that time when the urea nozzle got clogged really gave me a scare. The usual causes are crystallization of urea solution or impurity buildup. When adding urea, it's important to choose high-quality products to avoid cheap ones clogging the nozzle holes. If the nozzle does get blocked, I first try DIY methods: pour special cleaning agent into the urea tank, or remove the nozzle and soak it in warm water for cleaning. If that doesn't work, then it's off to the repair shop for technicians to clean it with professional equipment or replace it with a new nozzle. Never force the vehicle to run in this condition, as it might enter a torque limitation mode and become immobile. Prevention is key—I check the urea level every time I refuel and top it up periodically to keep the system active. For long-term parking, I occasionally start the engine to allow the urea to circulate through the pipes.

[OOlivia]

Having driven diesel pickups for over a decade, I've encountered urea nozzle clogging several times. The key lies in diagnosing the cause: either inferior urea solution forming clumps or sediment buildup from prolonged system inactivity. My approach is to first turn off the engine, remove and clean the nozzle – using a soft brush and cleaner carefully to avoid damaging components. After cleaning, reinstall and test. If issues persist, replacing the part promptly is advisable. For prevention, I only use reputable brand urea and inspect the injection lines every two months. Remember, unresolved clogs lead to SCR system failure, increased emissions, wasted fuel, and compromised driving safety. Addressing issues promptly saves both hassle and money.

[ArianaLynn]

As an ordinary office worker, when my car has problems, I always think about how to solve them in a convenient and cost-effective way. If the urea nozzle gets clogged, I immediately go to the gas station to buy a bottle of cleaner, pour it into the urea tank, let it soak for a few hours, and then rinse it out. This usually clears the blockage. The cost is low, less than a few dozen yuan. For prevention, I avoid parking in low-temperature environments for too long and regularly drive on the highway to keep the system running smoothly, preventing crystal buildup. If the blockage becomes severe, I can just go to a roadside repair shop instead of paying high prices at a 4S dealership for part replacements. Poor-quality urea is the main culprit, so I always choose high-quality solutions to reduce the risk of malfunctions. These small habits have saved me a lot of time and money on car repairs.