Hi, My name is*****'m happy to help you. During our conversation, I may be presenting you with different things to try, and ask you some Questions to get a better understand of the issue so I can answer your question properly. So stick with me to the end, and I am sure we should be able to get this issue resolved for you!
First thing you will need to do is drain the gas tank and clean it. Then you could possibly be looking at a fuel pump and all injectors. But I would start with the tank first and get the diesel out first. You shouldn't have hurt the engine, you will want to change the oil as well, cause the diesel is does not ignite in the cylinder and can wash out the cylinder walls and get into the oil
Figure 2 to 3 hours labor to get the gas out of the tank and see how it runs with good fuel. If you need a fuel pump, add a hour to the labor and the pump is around 300 or so. If you need all 4 injectors, you can add around 2 to 3 hours in labor and around 450 in parts.
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