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Q: Truck running rough

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My 06 f150 5.4L is running really rough after engine temp gets around 200 degrees. Any thoughts on what could be causing this?

My car has 122000 miles.
My car has an automatic transmission.

A: You may have a vacuum leak on the PCV hose ...

You may have a vacuum leak on the PCV hose to the intake manifold. Check the hose for any leaks at the connection of the hose at the intake port. If there is no leak then scan the engine and see if any codes are present.

If no codes are present then look at the mass air flow sensor to see if it is dirty from the air filter dirt. If you used one of those oil type of filters which contaminated it then you'll need to clean out the mass air flow sensor with some sensor cleaner. Afterwards, replace the air filter with a non oil type filter.

If you need some help with this, consider YourMechanic, as a certified professional can perform these checks to properly diagnose your rough running condition and repair it.

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