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Porsche Radiator Troubleshooting

Is your engine overheating because of a plugged radiator? How to troubleshoot a radiator fan which just won’t turn off? The radiator is the heart of a cooling system but surprisingly demands little maintenance. Most radiator problems arise from plugging, either inside the tubes or in the surrounding fins. When there is an issue with your cooling system you should always play it safe and ask an Expert for a solution. A neglected cooling system could prove an expensive exercise.

Read on for answers by Experts to a few radiator questions from users.

How often should the coolant be replaced on a sparingly used Porsche Cabriolet?

However little the car is run, coolant should be replaced at least once a year. As coolant ages it tends to decompose and produce harmful chemicals which are detrimental to the radiator, heater core and water pump, causing them to corrode from the inside.

Where could a significant coolant leak near the wheel well of a Porsche be coming from?

There are multiple sources for this type of coolant leak but the most likely are a leaking water pump or fractured engine radiator hose. A coolant pressure test will highlight the exact location of the leak. In due course, the coolant warning light will also come on. Once the leak is located and repair done, the system will need to be topped up with fresh coolant.

How to troubleshoot a Porsche 911 which emits a coolant odor after a drive, but displays no signs of leakage?

Open the radiator cap and top up the depleted coolant till full. Now inspect the system for leaks paying particular attention to the reservoir, hoses, radiator, and around the engine. If nothing can be seen then a pressure test will need to be done which, under pressure, should throw up the source of the leak. A pressure test is typically done on a cold engine which is turned off.

Why does a Porsche Cayenne radiator fan continue to run after the engine is switched off till it drains the battery?

The fan controller, which is part of the fan, has probably gone bad and will need to be tested. A diagnostic scan will reveal the exact nature of the fault. This will tell whether the problem is caused by the signal between fan controller and engine computer, or whether it is with the controller itself.

Why has a Porsche Cayenne radiator fan suddenly become abnormally noisy?

The radiator fan is designed to kick in when the engine reaches a certain temperature or when the AC is switched on. If the engine temperature goes excessively high, or if the outside air is extremely hot, the fan may run at peak speed causing the noise that is being heard. However, if this sound was never there earlier, it could be that the fan motor bearings have failed resulting in an abnormal whining sound. The best way to know if the radiator fan is faulty is to compare it with a similar fan in another vehicle.

What do traces of oil in a Porsche Boxster S radiator and radiator hoses imply?

Check for exhaust gases in the cooling system which will generate excessive radiator pressure, because of which the coolant temperature will rise. Also, check if there is any blockage in the system which is usually evident by cold spots in certain areas indicating lack of circulation. In the worst case, the problem could be due to a cracked cylinder head or a blown head gasket.

Which sealing product can be used to repair a coolant leak in a Porsche radiator?

Sealing products and other additives are frowned upon as repair agents. While these sealants are designed to seal holes they often seal the coolant channels in the system as well, causing more damage to the engine.

Is coolant sludge mixed with oil caused by a radiator leak and if so, what is the next step?

When coolant mixes with oil it is not because of a faulty radiator but a red flag for a blown head gasket. The cylinder head will need to be removed to assess the damage.

How to troubleshoot a Porsche 944 radiator fan which cuts in after a while when idling but does not cut out again?

Chances are that the thermostat is not opening sufficiently to cut the fan out. Flush out the old coolant and refill the radiator with fresh coolant. Also, change the coolant thermostat and run the engine again. If there is no improvement then the radiator could be partially plugged. If there is partial blockage, some sections of the radiator, where coolant does not circulate, will remain cool. The radiator fan will blow air at differential temperatures.

Cooling system failure will bring a car to a halt, but some failures could have more serious engine-damaging consequences like a cracked cylinder head, for example. At the first sign of a cooling system problem or a radiator related issue, it pays to ask an Expert for help. Experts will answer all Porsche radiator related questions and provide information on Porsche radiators.

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