Q: How can you tell if you have an intake manifold leak verses blown head gasket ?

asked by on January 15, 2017

We have a 2004 Chevy Silverado it's been leaking coolant it looks from driver side wheel well today I went to check oil and there was no white milky stuff on dipstick but when I removed oil cap there was white milky film

My car has 243000 miles.
My car has an automatic transmission.

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Due to condensation within the engine, whitish discoloration on the underside of the oil cap is not unusual. If the oil in the oil pan is not coolant contaminated, you need not worry. If you have an external coolant leak, the source (intake versus head gasket) can be distinguished by pressure testing the coolant system and/or using special UV dyes that are added to the coolant. If you desire that a coolant leak be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an engine coolant leak diagnostic and the responding mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.

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