There are a few potential causes for rough idle and smoke during acceleration in a Geo Metro 1 liter:
1. Spark Plug Issues: Worn or fouled spark plugs can cause the engine to run rough and misfire, leading to vibrations, and excessive smoke. Check the spark plugs for signs of wear or deposit buildup and replace them if needed.
2. Faulty Ignition System: Problems like a faulty distributor, ignition coil, or ignition wires can disrupt the proper timing of sparks and cause rough idle and smoke. Inspect these components and ensure they are functioning correctly.
3. Fuel Injection System Issues: Malfunctioning fuel injectors or a clogged fuel filter can disrupt the proper fuel supply, resulting in rough idle, hesitation, and smoke emission. Check your fuel injectors and fuel filter for any issues.
4. Vacuum Leaks: Leaks in the vacuum lines can cause the air-fuel mixture to become too lean, leading to a rough idle and excessive smoke. Inspect all vacuum lines for any cracks, breaks, or loose connections, and fix them as necessary.
5. Engine Compression Problems: Worn piston rings or other internal engine issues can lead to low engine compression, causing the engine to run rough and produce smoke. To check for compression problems, perform a compression test on your engine.
6. EGR System Issues: A faulty or clogged EGR (Exhaust Gas Recirculation) system can lead to rough idle and smoke emissions. Check the EGR valve for proper operation and make sure there are no obstructions in the EGR passages.
7. PCV Valve Issues: A malfunctioning PCV (Positive Crankcase Ventilation) valve can cause a rough idle and smoke, as it affects the proper flow of air and vapors in the engine. Check the PCV valve for proper operation and replace it if necessary.
Note: Since diagnosing the exact cause of rough idle and smoke requires a hands-on inspection of the vehicle, it is recommended to seek assistance from a qualified mechanic or an experienced do-it-yourselfer.
