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Q: Engine swapping on a Subaru

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I'm interested in engine swap on my Subaru. If it's cold outside, it starts up fine, but if it's hot or the car has been running for a while, it takes multiple times before it turns over. Car runs fine if it starts. The compression is good.

When the car starts cold, it needs extra fuel. That’s just how the cars work. So if you have a normal car that is running perfectly and when you turn the key, the computer sends extra pulse to the fuel injectors so it starts when it is cold.

If your car starts fine when it is cold, but then when it’s hot, it doesn’t start and you’ve got to crank it over. That generally means that the fuel injectors are probably leaking or the fuel pressure regulator’s leaking. Because a hot engine is hard to start if it has too much fuel. It doesn’t need extra fuel. So you probably have a leak in the fuel injection system somewhere. Have the car looked at by a professional so they can locate the leak and make the repairs needed to resolve this issue.

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