Why doesn't the automatic transmission car move when shifting to R gear without stepping on the accelerator?

[Paul]

Automatic transmission cars not moving when shifting to R gear without stepping on the accelerator may be due to rusted brake discs or dirty transmission fluid. Rusted brake discs: If the brake discs are slightly rusted, it increases the resistance of the wheels. Polishing the brake discs can solve this issue. Dirty transmission fluid: If the transmission fluid is dirty or the clutch is slipping, it can cause this situation, and the transmission fluid needs to be replaced. Brake disc replacement cycle: Inspect the front brake discs every 60,000 kilometers and the rear brake discs every 120,000 kilometers. The maintenance cycles specified by different car manufacturers may vary, so the specific replacement cycle should follow the manufacturer's requirements. Transmission fluid replacement cycle: Under normal usage, for manual transmission vehicles, it is recommended to replace the transmission fluid every 3 years or 60,000 to 80,000 kilometers. For automatic transmission models, the transmission fluid should be replaced every 2 years or 40,000 to 60,000 kilometers. If the transmission has undergone repairs, especially major repairs, it is strongly advised to replace the transmission fluid every year or after driving 20,000 kilometers.

[Evelyn]

I've been driving automatic transmission cars for many years and often encounter the issue where the car doesn't move when shifted to R gear without pressing the accelerator. This is usually caused by low idle speed. It's particularly noticeable during cold starts when the engine RPM isn't high enough to drive the transmission torque converter. Throttle carbon buildup is a common cause - excessive carbon deposits restrict air intake and lower idle speed. Some vehicles are more prone to this when going uphill. Insufficient transmission fluid pressure can also be the culprit, whether due to dirty fluid or leaks. My advice is to let the engine warm up for a few minutes after a cold start before trying again. If the problem persists, get it checked at a professional shop immediately - don't wait until it causes major trouble like stalling while reversing and hitting a wall. Safety first, don't skimp on maintenance costs.

[DallasLee]

Having worked in the auto repair industry for a long time, I've encountered many cases where the car doesn't move when shifted into reverse gear, with the root cause mostly lying in the power transmission system. The torque converter may not be locked properly, or internal transmission components could be worn out, leading to insufficient torque at idle. The engine idle speed setting being too low is another possibility, and faults in the oil pump or throttle position sensor can affect power output. Additionally, bugs in the electronic control unit can cause the system to misjudge. For DIY checks: first, ensure the brake is fully released and the car is on level ground; start the engine and listen for unusual noises; check the transmission fluid level and color—if it's cloudy, it needs replacement. Regular maintenance is crucial, especially for older vehicles where transmission fluid should be changed at least every 40,000 kilometers to avoid costly repairs.

[EmersynFitz]

I just bought my first automatic car last year and was initially troubled by the lack of movement when shifting to R. Later, the mechanic told me it's normal, as most cars have minimal reverse power at idle, especially on slopes or uneven roads. However, if this happens repeatedly, it might indicate minor issues like engine carbon buildup or a faulty idle control valve. Remember that turning on the AC or heating system increases the load, making this phenomenon more noticeable. It's more reassuring to promptly visit the shop for a diagnostic scan of trouble codes. Delaying could lead to more severe transmission damage or even engine stalling and vehicle sliding, causing accidents.