Q: oil light came on and accidental dumped 1/2 quart of oil in the rad before I realized it. Siphoned off a little more than a 1/2 ga

asked by on May 03, 2017

Accidentally put a half quart of oil in the Radiator. Siphoned to a 1/2 gallon of the now mix then put back new coolant. Drove the car down to the mechanic ( 10 miles) ran fine. Explained what happened and asked him to flush everything. He flushed it three times until no sign of oil in radiator. The problem now the dash warning light comes on after 10-15 mins of idle run time stating the engine is overheating , shut down. The dial dash gauge shows normal temps. Your thoughts?

My car has 85000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. If you did not get all of the oil out of the radiator before you started the vehicle, that oil is now contaminating the thermostat, water pump, and the engine cooling pockets. Even with several flushes, these components may have been permanently affected. Considering the check engine light is on, you want to know what it is trying to tell you. Have the vehicle scanned for codes, as it may tell you what sensor or component is having issues. Considering the overheating issue, it is possible the thermostat is not opening due to contamination, the water pump is not pumping fast enough, the cooling passages in the engine which fill with coolant are clogged, or that the radiator is clogged somewhere. Only further inspection will tell. For help with testing, contact our service department to schedule an appointment.

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