Daewo Lanos2002

Good afternoon. My car is idling roughly. I checked the ground wires to the engine and found two loose black wires. When I connect one of them, the idle stabilizes, but the car doesn't move. When I connect the other wire, the rough idling returns. Can anyone help me with a wiring diagram? Or with the information I need to solve this problem? It's urgent. Thank you.

You should specify a bit more, whether the vehicle moves at all, or if it's just an unstable idle. I would start by checking the vehicle's data: is the mixture rich or lean? Is the TPS signal fluctuating even without touching the accelerator? It could be a missing ground connection, or in cases with only one oxygen sensor, the sensor might be faulty, as with the Chevy Monza. Another thing you could do is disconnect the MAP sensor, if it has one. Fuel injection systems vary between countries, and it might have a different type of air sensor. But for me, analyzing live data from the vehicle is much more helpful for diagnosing a problem.

Have you checked the engine's firing order? The spark plug wires (thick black wires) might be connected incorrectly. The firing order is 1-3-4-2 , not 1-2-3-4. This is basic, but not everyone knows it and connects the wires randomly. You should look for stability of movement,

but the issue of misalignment could be due to the clutch system, either worn or improperly adjusted.