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Q: What is wrong with my car? on 1993 Jeep Grand Cherokee

I put a motor in my car and it is now jumping when I crank it up and when I take off it jumps when you give it yo gas. When you get it on the highway it is fine until you get it up to 55 sometimes it will start shaking all over the road! What do I need to fix?
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If the engine itself is jumping when cranked or when given gas it sounds like there is either a motor mount bolt missing or the motor mount is broken. Check you motor mounts.
Are any warning lights coming on when this happens? Did a shop recently do the engine swap for you? Maybe you can take it back if they missed something during the installation
If your dad has a fuel pressure gauge (or can rent/borrow one), that would be the best thing before replacing the fuel injectors I think. The Jeeps have a schrader valve on the fuel rail that allows you to drive around with the gauge and monitor pressure when you experience the symptoms. You can also see if the fuel pressure is bleeding off after you shut the engine off (this will tell if you have a leaking injector or some other internal leak).

It's also a good idea to test the coil, ignition wires, and check the distributor cap and rotor

If it were me I'd be double checking all my wire connectors and vacuum lines. I'd also make sure I put the spark plug wires on in the correct order

Do you see black smoke when this happens or are there other symptoms when you experience this bucking/surging?
Hey I just saw your other question, a problem that only happens when the engine is cold can be related to temperature sensors. Many times these are tested by checking their resistance at certain temperatures (if you don't have a scan tool to monitor that)

I'm happy to give you any ideas I can come up with.
My father put the motor in. He told me the next thing to do is the injectors but i now injectors cost a lot and I wanted to no if any one could think of anything else it could be.
Thank you so much for trying to help me. There is not any smoking or anything in that nature. When my father gets home I will have him to check all of the wire and everything and I will let you know what it is doing after that. Thanks so much again!!!
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