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Car will start but won’t take gas when press on accelerator, what may be the problem
Kelly Royal since you already replaced the engine and transmission, there could be plenty of reasons for the why. I’d start with checking the fuel supply lines and fuel filter. If you have the tools you can also check the fuel pressure. Check your throttle body to see if everything is functioning properly. This could also be a computer problem and might require a rest/flashing for new software etc. If it is somewhat driveable etc. I’d get the OBD scanned to see if it throws any codes. You did not tell us if your service engine light is on, the exact year, model and engine size. Let us know what you find.