* Engine Mounts: Worn or broken engine mounts allow excessive engine movement, leading to shaking, especially under acceleration when the engine is under load. This is one of the most common causes.
* Transmission Issues: Problems with the transmission, such as worn or damaged mounts, low transmission fluid, or internal transmission problems can cause vibrations that transfer to the engine and the rest of the car.
* Driveshaft Problems: A bent or unbalanced driveshaft can induce vibrations throughout the drivetrain, particularly noticeable during acceleration.
* Uneven Tire Wear or Pressure: While less likely to cause significant shaking, uneven tire wear or incorrect tire pressure can contribute to vibrations that might feel like engine shake. Check your tires for wear and ensure they are properly inflated.
* Spark Plugs/Wires: Faulty spark plugs or ignition wires can cause misfires, leading to a rough running engine and noticeable shaking, especially during acceleration.
* Oxygen Sensor: A malfunctioning oxygen sensor can cause an incorrect air/fuel mixture, leading to rough running and shaking.
* Mass Airflow Sensor (MAF): Similar to the oxygen sensor, a faulty MAF sensor can provide incorrect information to the engine computer, resulting in a poor air/fuel mixture and shaking.
* Balance Shaft Issues (If Equipped): Some engines have balance shafts to reduce vibrations. A problem with these shafts can cause increased vibrations.
* Internal Engine Problems: While less common, problems like worn piston rings, connecting rod issues, or other internal engine damage can lead to significant vibrations and shaking. This is typically accompanied by other symptoms like loss of power or unusual engine noises.
Troubleshooting Steps:
1. Check Engine Mounts: Visually inspect the engine mounts for cracks, tears, or excessive wear. A mechanic can easily assess their condition.
2. Check Transmission Fluid: Ensure the transmission fluid is at the correct level and condition. Low or dirty fluid can cause problems.
3. Inspect Driveshaft: Look for any obvious damage or misalignment in the driveshaft. This often requires professional inspection.
4. Check Tires: Inspect tire tread for uneven wear and ensure proper inflation.
5. Have a Diagnostic Scan Performed: A diagnostic scan can identify any trouble codes stored by the engine computer, which can pinpoint the source of the problem. This is highly recommended as a first step.
If you're not comfortable diagnosing and repairing these issues yourself, it's crucial to take your 1994 Chrysler LHS to a qualified mechanic for proper diagnosis and repair. Ignoring the problem could lead to more significant damage.
