VW Bora Radiator Fan Failure Causes Engine Overheating

Had similar issues with my 2003 VW Golf 1.8T. The radiator fan not engaging properly was a major red flag. Initially thought it was just the fan blade or a simple thermal switch, but diagnostic tests revealed a failed fan motor and a faulty engine cooling temperature sensor. These symptoms match exactly what you described, inconsistent temperature readings, constant overheating, and CEL activation. The radiator fan should typically kick in when engine temperature reaches operating level, but a defective sensor can prevent proper fan engagement. This was a serious issue that required immediate attention. Continued driving with these symptoms risks severe engine damage through overheating. The repair involved replacing both the fan motor assembly and temperature sensor unit. The failing fan motor was causing irregular cooling patterns, while the faulty sensor was sending incorrect signals to the ECU. The cooling system in these VW engines is quite complex and interconnected. When the fan noise becomes inconsistent or stops completely, its often more than just a mechanical fan blade issue. The entire engine cooling system needs thorough testing to identify all compromised components. Would strongly recommend getting this checked by a qualified mechanic familiar with VW cooling systems, particularly given your mileage and model year.

Thanks for sharing your experience with the VW Golf cooling issues. Glad you caught both problems before any major engine damage occurred. My Bora also needed similar repairs and has been running fine since the fix. Quick follow up: what was the total cost for your fan motor and temperature sensor replacement? Just curious since I had to swap out my entire car radiator assembly. Also, have you experienced any other cooling-related problems since the repair? Just want to compare notes since these VW cooling system problems seem pretty common from what I have read in other threads.

After replacing the faulty radiator fan motor and speed sensor, my Golf has been running perfectly with no cooling issues at all. The repair bill came to 250€ for the speed sensor replacement, which was the main culprit causing the erratic temperature readings and fan behavior. The fix completely resolved the car overheating problems. The thermal switch and cooling system now work exactly as they should. You can clearly hear the radiator fan kick in at the right temperature points, unlike before when it was barely running. Your case sounds more extensive since you needed the full car radiator assembly replaced. My repair was simpler since we caught it before any additional components were affected. In the 6 months since the fix, the temperature gauge has remained steady and the fan engages consistently during normal operation. A properly functioning cooling system really makes a difference in these VW engines. Regular maintenance checks help catch these issues before they escalate into more costly repairs.

Truly appreciate all the insights shared here. After checking with my trusted mechanic, they confirmed similar findings to your Golf, but my case needed more work. The full radiator assembly replacement ended up costing 850€, including labor. Quite steep, but necessary given the extent of the damage. The repair process took about 6 hours total. They found the engine cooling system had multiple failing components, not just the thermal switch and fan blade issues I initially suspected. The radiator fan had completely seized, and there was significant corrosion in the old assembly. Since the repair two months ago, the car runs perfectly. The temperature gauge stays steady, and I can actually hear the radiator fan kicking in properly now. No more check engine lights or overheating problems. Worth every cent to avoid potential engine damage. Understanding these common VW cooling system issues definitely helped me make a more informed decision this time around. Thanks again for helping me understand what I was dealing with.