Engine torque at 800-1200 RPM is insufficient to move from a stop. I have driven manual transmission vehicles from small cars to heavy trucks (54,000 GVW) since 1964. All can move from a stop at idle as the clutch begins to achieve friction. The American Automobile Association instructs drivers of manual transmissions to begin to release the clutch until reaching the friction point. At that point, the vehicle begins to move on flat ground. Continue to slowly release the clutch until the vehicle is moving. At that time, apply the gas to accelerate. This is the technique I have used and taught for over 60 years of driving.
The drive-by-wire system in the 2020 Wrangler fails to deliver sufficient fuel / torque to use this method. One must rev the engine to 1500 + RPM (higher on hills) to move from a stop. Worse, the fuel systems does function correctly about 60% of the time. Thus, when one expects the system to function correctly for a smooth low RPM move off, the engine stalls unexpectedly or requires the clutch to be rapidly depressed and slipped while the engine must be reved.
I have discussed this with my dealer several times. Each time the response has been, "Fiat paid millions for this system. It is good. That's just the way it is." This is unacceptable. I know from many hundreds of thousands of miles of driving the compensatory technique of reving the engine and slipping the clutch will result in pre-mature clutch failure. The inconsistent accelerator / engine response results in unexpected stalls. This is automotive design incompetence that may also be dangerous.
Engine torque at 800-1200 RPM is insufficient to move from a stop. I have driven manual transmission vehicles from small cars to heavy trucks (54,000 GVW) since 1964. All can move from a stop at idle as the clutch begins to achieve friction. The American Automobile Association instructs drivers of manual transmissions to begin to release the clutch until reaching the friction point. At that point, the vehicle begins to move on flat ground. Continue to slowly release the clutch until the vehicle is moving. At that time, apply the gas to accelerate. This is the technique I have used and taught for over 60 years of driving.
The drive-by-wire system in the 2020 Wrangler fails to deliver sufficient fuel / torque to use this method. One must rev the engine to 1500 + RPM (higher on hills) to move from a stop. Worse, the fuel systems does function correctly about 60% of the time. Thus, when one expects the system to function correctly for a smooth low RPM move off, the engine stalls unexpectedly or requires the clutch to be rapidly depressed and slipped while the engine must be reved.
I have discussed this with my dealer several times. Each time the response has been, "Fiat paid millions for this system. It is good. That's just the way it is." This is unacceptable. I know from many hundreds of thousands of miles of driving the compensatory technique of reving the engine and slipping the clutch will result in pre-mature clutch failure. The inconsistent accelerator / engine response results in unexpected stalls. This is automotive design incompetence that may also be dangerous.
- Robert H., Littleton, US