In response to the motor with the bad shake its a 1992 240sx ka24de 2.4 liter dohc 4 cylinder just did a motor swap shakes really bad during idol when the motors warm its still shaking?

Answer 1

In general, engine "shaking" is caused by a misfire in one or more cylinders. That can be caused when a multiport injector is plugged or faulty, a plug wire or sparkplug is faulty or one or more cylinders have low compression. Try to isolate the cylinder that's not firing. Plastic pliers are available for pulling plug wires. Pull one plug wire at a time and see which one DOESN'T make a difference. When you pull the plug wire from a cylinder that's running, that cylinder will stop firing and the engine will run worse. If you come across a cylinder that was already misfiring, the engine won't run any worse by disconnecting the plug. Once you've isolated the cylinder, check the plug. If it's fouled or wet, it's possibly an ignition problem, check the wire(s) and possibly replace the plugs. On the other hand, while you have the plug out, check the compression on that cylinder, it should be above 100 PSI, or at least very near to it. If the plugs are good, and the compression is up, start being suspicious of the injector.