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Q: I get 5 miles per gallon truck stalls at low rpms

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I get 5 miles a gallon it stalls when coming to a stop or at low rpms it shakes or vibrates. In drive in neutral it smooth out it cranks abit before. It starts but it always starts. Has new plugs wires cap rotor ....timing chain and radiator. Were replaced at 120k it now has 176k. There is a strong smell of gas but no leaks I mean strong a guy behind me In traffic going 60 at light told me he could smell gas

My car has 176000 miles.
My car has an automatic transmission.

A: This may be a sign of a failing idle air co...

This may be a sign of a failing idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine. This valve is controlled by the vehicle's computer, which will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. The purpose of this valve is to allow the engine to return to a normal idle speed after the engine RPMs have been increased. This valve slowly controls the air/fuel mixture going into the motor to return the engine back to a slow speed or idle. However, when the engine RPM drops below the normal range of 750-800 RPM (for most cars) the vehicle may stall as you have experienced and this may indicate a dirty or faulty idle air control valve. This may also cause poor fuel mileage as you have also experienced. I would recommend having an expert from YourMechanic come to your home to replace your idle air control valve.

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