Q: the car will not go past 30 mph without missing.

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the car will not go past 30 mph without missing, cutting out or just flat out dying on me. ive already replaced the ignition coil spark plug and wires, fuel pump and filter.

My car has 115000 miles.
My car has an automatic transmission.

Hi there. Sounds like the engine has either a major vacuum leak or a burned valve. Check all the vacuum lines and ports for any signs of leaks. Check the brake booster and see if it has a leaking check valve. Check the engine for a burned valve by performing a compression test and leak down test. If you need further assistance with your engine not accelerating past 30 mph without cutting out, then seek out a professional, such as one from Your Mechanic, to help you.

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