What Causes the Warning of Water in Fuel for Diesel Vehicles?
2 Answers
There are many reasons why a diesel vehicle may indicate water in the fuel: leakage from the water seal (for engines equipped with one), damage to the water channel cover, cylinder head gasket failure, or cracks in the engine block, cylinder head, or cylinder liner. If the engine is functioning normally, the possibility of a cylinder head gasket failure can be ruled out. For engines with a water seal, the oil pan can be removed to check if the water seal is leaking (without draining the water). If the water seal is intact, further troubleshooting is required. Below is an introduction to automotive urea: 1. Origin: Automotive urea solution was first used in Europe, where it is called AdBlue. In North America, it is referred to as DEF (Diesel Exhaust Fluid). In China, it is known as automotive urea solution or "automotive denitrification agent." However, it is now commonly referred to as "automotive urea" in China. 2. Function: Automotive urea solution is crucial for reducing pollutant emissions from diesel vehicles. It is a urea-based chemical reagent, composed of high-purity urea and deionized water, forming a 32.5% concentration solution. The application of automotive urea solution in SCR systems is key to ensuring that engine exhaust emissions meet China IV and higher emission standards.
Last time my friend's car had a similar issue, and I helped him check some common causes. The main reasons might include water in the fuel system, a problem with the fuel tank sealing, or the water-in-fuel sensor being triggered. Specifically, for diesel vehicles, water can mix into the fuel tank when refueling on rainy days, or the gas station's storage tank might have residual water. Another common issue is aging fuel cap seals, allowing rainwater to seep in. Additionally, diesel engines naturally produce condensation during operation, and if the water separator filter isn’t replaced for a long time, excessive water can accumulate. Moreover, water at the bottom of the fuel tank tends to trap debris, leading to excessive moisture levels. If not addressed promptly, water can corrode the fuel pump and injectors, shortening the engine's lifespan. So, as soon as you see the warning, check the water separator and drain it. It’s recommended to perform fuel system maintenance every six months to prevent minor issues from becoming serious.
