Q: Why is my car not accelerating Normal

asked by on September 27, 2017

got a tune up, new icm. Same coils though. The car accelerated to 30 then slowly goes past 30. However when I press down on the gas about halfway. It accelerates past 30 faster. Not a normal fast but a good speed. What would be the problem ? Also I hear this sound like metal discs are sliding against each other and another sound in the mornings like a crank noise. Like I can't build up enough speed to get on the freeway. I've gotten on once when it was slow. And I got over 70 eventually. It revs normal. Doesn't over heat

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The metallic noise could arise from a variety of sources; anything from the brakes to the engine. The origin could definitely be pinpointed by a certified mechanic during a vehicle noise diagnostic. Slow acceleration has a variety of causes. Fuel injectors can become clogged over time as the tiny passages become clogged. When an injector is clogged it can degrade the performance of the vehicle and the car may accelerate slowly or feel that it does not have enough power. Other symptoms include a rough idle, a vehicle that is hard to start and a decrease in fuel efficiency. A defective fuel pump will not supply enough fuel to the injectors. This can cause the vehicle to accelerate slowly, or even sputter and stall, especially at high speeds. A clogged fuel filter can also restrict the amount of fuel that reaches the injectors. A dirty airflow sensor can cause the wrong data to be be sent to the computer. A slow accelerating car is the result of this incorrect data. It may also trigger the Check Engine Light. Other causes of poor acceleration are vacuum leaks, a defective throttle position sensor and a defective idle air control valve. To get the underlying cause of the poor acceleration pinpointed and resolved, the recommended service is an engine diagnostic for slow acceleration. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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