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I have a 2007 Tahoe 5.3 flex fuel. I replace front brakes…

Customer Question
I have a 2007...

I have a 2007 Tahoe 5.3 flex fuel. I replace front brakes and when I was ready to start the truck, alot of white smoke like clouds came from exhaust pipes. Check oil and water and oil is not milky.

Mechanic's Assistant: Has the vehicle turned into a gas hog? And how does it start -- same as usual?

Normal and no engine noise

Mechanic's Assistant: Are you fixing your Tahoe yourself? What have you tried so far?

I have not started anything, just looking to see what I can do. The only thing that I did is cylinder tester.

Submitted: 7 months ago.Category: GMC
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Answered in 1 minute by:
12/6/2017
GMC Mechanic: Mike S., ASE Certified Technician replied 7 months ago
Mike S.
Mike S., ASE Certified Technician
Category: GMC
Satisfied Customers: 8,101
Experience: GMC N.A.I.S.E. Certified Auto-Mechanic
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Hi, I am Mike, welcome. I'm reviewing your question.

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GMC Mechanic: Mike S., ASE Certified Technician replied 7 months ago

What is a cylinder tester and what were the results?

You may have a leaking fuel injector and the white smoke was raw gasoline burning off once the engine started.

After letting the engine sit for awhile again, remove all the spark plugs and smell if any smell like gas. If you find one, that will be the cylinder that has a leaking fuel injector.

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GMC Mechanic: Mike S., ASE Certified Technician replied 7 months ago

If the smoke is still there, it may be a blown head gasket and it just hasn't been blown long enough for the classic signs of milky oil.

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GMC Mechanic: Mike S., ASE Certified Technician replied 7 months ago

Don't forget to rate me well, so I get credit. If you don't, the deposit you made will just sit there and I won't get my share of it.

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