I have an older car and sometimes, without any warning, it will go only around 5 mph. This problem only occurs at low speeds. When it drops to the 5 mph phase it lasts for 30 seconds to a minute and then it will return to normal functioning again. There are some times when it will not accelerate at all. In your professional experience, what is causing this and is it fixable?
Your description sounds like a fuel starvation problem. Checking fuel pressure will be a good place to start. A clogged fuel filter, failing fuel pump, failing or clogged fuel pressure regulator, or clogged fuel injectors could all cause this behavior. A professional mechanic, like one from YourMechanic, can help diagnose and repair this problem.
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