Hello John, the combination of symptoms you describe suggests a serious problem that requires immediate attention. Since the overheating occurs within a minute or two of driving and is accompanied by multiple warning lights, a loss of power, and a snapping noise, I advise against continuing to drive the vehicle until it has been properly diagnosed.
It is important to understand that many modern vehicles are programmed to protect themselves when the engine overheats or when critical systems fail. When the engine control module detects abnormal temperatures or other serious faults, it can reduce engine power, disable certain features, and illuminate multiple warning lights. Therefore, while the ETC, engine, SERV 4WD, and oil lights are all activating together, they may not necessarily indicate separate faults; rather, they could be secondary warnings triggered by a primary issue.
One likely cause is a failure in the accessory drive belt system. The snapping sound you hear during acceleration is a significant clue. If the serpentine belt is slipping, damaged, or intermittently losing tension due to a worn tensioner or a seized pulley, several systems can be affected simultaneously.
The belt drives important components such as the water pump, alternator, and air conditioning compressor. If the belt does not effectively turn these components, the engine can overheat quickly, the battery may not charge properly, and the AC might stop cooling effectively.
Another strong possibility is a failing water pump. Even though you replaced the radiator, the cooling system is only as effective as its weakest component. If the water pump is damaged or its impeller has failed, coolant may not circulate properly through the engine, causing temperatures to rise rapidly after startup, even when coolant levels appear normal.
The thermostat should also be inspected. If the thermostat is stuck closed, it will prevent coolant from flowing between the engine and radiator. In such cases, the temperature gauge can move from normal to dangerously hot within a very short time. While thermostats are relatively inexpensive components, they can cause severe overheating if they fail.
The oil warning light is particularly concerning. In some vehicles, this light may illuminate due to extreme engine heat affecting oil pressure readings. However, it could also indicate a genuine oil pressure problem. Low oil pressure can result from insufficient oil, a failing oil pump, clogged oil passages, or internal engine wear. If the engine is genuinely losing oil pressure, continuing to drive could lead to catastrophic engine damage.
You should also consider the possibility of a failing engine cooling fan. If the fan is not functioning correctly, temperatures can rise rapidly, especially in traffic or at low speeds. However, given that your vehicle overheats within about a minute of driving, I would first focus on issues related to coolant circulation and the drive belt before suspecting the cooling fan alone.
Another area that deserves attention is the vehicle’s electrical and computer systems. Modern vehicles rely on sensors to monitor coolant temperature, throttle position, oil pressure, and various other functions.
A faulty sensor or wiring problem can sometimes trigger warning lights and force the vehicle into a reduced-power mode. However, electrical faults alone typically would not explain the rapid overheating and snapping noise, which is why a mechanical inspection should take priority.
The fact that the vehicle struggles to crank is also important. This could indicate that the engine has been under stress from repeated overheating episodes. It may also point to charging system issues if the alternator is not functioning properly due to a slipping belt.
My recommendation is to have a technician inspect the serpentine belt, belt tensioner, pulleys, water pump, thermostat, and cooling system immediately. A diagnostic scan should also be performed to retrieve any stored fault codes from the engine control module. These codes can provide valuable clues about why the ETC, engine, and SERV 4WD warnings are appearing.
Please do not ignore the oil warning light or continue driving the vehicle while it is overheating. Severe overheating can warp cylinder heads, damage head gaskets, seize pistons, and lead to complete engine failure. The sooner the root cause is identified, the better the chances of avoiding an expensive repair.