I just recently replaced my transmission and today for some reason it doesn't really want to start. When it does and I throw it into drive it slams into gear and stalls. Why is this?
My car has an automatic transmission.
It sounds like there are two issues, one is the hard starting and two is the harsh engagement. The hard starting obviously has to be resolved first. Although there are many causes of harsh engagement, it is possible that high idle speed once you do get the engine running is a factor here. There are many causes of hard starting but illustrative ones are a faulty engine coolant temperature switch (sensor), worn spark plugs, inadequate fuel delivery or pressure (e.g., clogged fuel filter), dirty fuel injectors, contaminated or old gasoline, malfunctioning idle air control valve, poor engine compression, and so forth. You can identify the specific cause of the issue that you are writing in about by requesting a hard starting diagnostic and the responding certified mechanic will get this resolved for you. Once that issue is resolved, the same mechanic will diagnose the harsh engagement, if the problem still exists. 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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