Q: Car will not go over 40 MPH

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I first noticed the problem when my Check Engine light came on. At this time, my car could not go over 80 MPH. Over time, the maximum speed dropped to 60 MPH and then 40 MPH. Basically, my car jolts every time I go over 1,500 RPMs. I can switch gears at this point to make the jolting go away, but I am barely reaching 40 MPH in fifth gear. If I try to give it more gas it jolts. Other than that my engine runs good.

I have seen this same scenario many times. The problem I believe is from a clogged catalytic converter. When they become clogged they restrict the flow of exhaust gas and the engine can not operate efficiently. I would recommend having a technician, from YourMechanic, to come inspect your vehicle’s Check Engine Light and replace your catalytic converter if needed.

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