Q: Car overheating within seconds

asked by on January 30, 2017

Hi. Driving home Monday, suddenly heat gauge needle flew to RED and light came on. Fan engaged later than usual. Switched off engine immediately, waited till engine cool, checked oil and water. Levels perfect, no moisture in oil, no oil in water. Once cooled, drove home. Next day car to mechanic. Said pipe blocked. Flushed. Fetched car Wed. Within 45 seconds needs went from 0 to quarter, back to 0, back to quarter then settled on 1/2. Back to mechanic. Says Temperature Switch COULD be faulty. Thursday, bought new Temperature Switch + Fan Switch + Thermostat. New parts in, car still hot within seconds. Now mechanic says only 1/2 radiator getting warm - one side pipe warm, other side pipe cold. Says to "Chemically Flush" radiator. At my wits end. Dunno what next. Please can you advise me. Tx Ang

My car has 78000 miles.
My car has a manual transmission.

Sudden up and down fluctuations in the engine coolant temperature gauge signify a gauge, sensor, or wiring fault. To resolve that problem, the service to request is a temperature gauge diagnostic. The radiator could be partly cold if the water pump is not working properly. Prior to condemning the radiator, it has to be flow tested and/or it has to be determined if coolant is actually circulating. The most common causes of overheating include low coolant level, a faulty thermostat, a plugged radiator, a faulty radiator pressure cap, collapsed hoses, non functioning cooling fans, and a faulty water pump or drive belt. Certain engine faults, such as a leaking head gasket or poor engine running condition can also cause overheating. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an engine overheating diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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