If you spot a crack on your car’s plastic radiator, using a specialized kit to weld it back together is the most cost-efficient solution for radiator repair. However, since any coolant puts a lot of pressure on your radiator while your car’s in use, any small hole you leave on the weld will quickly widen and become a huge problem. To ensure that you fix a problematic weld on your car’s plastic radiator as soon as possible, watch out for these three signs. Engine Randomly Gets Louder After It’s Been On For Awhile If coolant is leaking out of your radiator while your car is on, there’s less coolant available to cool down your engine. While most weld leaks aren’t serious enough to dramatically impact radiator performance, they can still cause periodic engine heat flareups. So don’t ignore it when your engine consistently gets louder for a short period after it’s been on for a long time. Instead, immediately shut off your car, open your hood, and make sure that there are no leaks or cracks on your radiator weld. Your Air Filter Suddenly Stops Working Very Well Your car’s engine isn’t the only thing that can be affected by a crack in your plastic radiator weld. Since your car’s air filtration system is also located in the hood, it can be damaged by air that’s tainted with evaporated coolant. If the fuel going into your engine becomes tainted with debris soon after you weld your plastic radiator, you should review your weld before you assume that anything else caused the problem. The most obvious symptom of tainted fuel is a drop in your car’s gas mileage. Your Radiator’s Coolant Level Quickly Drops In order to ensure that your engine runs as efficiently as possible, it’s prudent to change out your radiator fluid. While coolant certainly becomes contaminated and ineffective over time, there’s no reason that much of it should disappear entirely from your radiator. The most likely explanation for a sudden and dramatic drop in your radiator’s coolant level is some kind of leak. The amount of coolant that vanishes from your system will closely correspond to how large and extensive the cracks on your radiator are. So if you only find a tiny crack on your weld, don’t be afraid to examine the rest of your radiator for imperfections. When the job is done right, fixing a crack on your car’s plastic radiator with a welding kit can be a very rewarding experience. But if it turns out that your weld has one or more cracks on it, it’s important that you realize your mistake and decisively fix the problem as soon as...