I experience a random intermittent problem that occurs when I go to accelerate from a traffic signal the speedometer stays at zero and my automatic transmission feels like it hasn’t “caught” on and is stuck in first. The car moves forward at a very slow speed (ie. Maxing out in first) even if I fully depress the gas pedal. I then nurse the vehicle to the side of the road, come to a complete stop with the brakes, and then it drives just fine after that. Occasionally it happens while decelerating and then re-accelerating in traffic, which is sometimes dangerous.
My car has 90000 miles.
My car has an automatic transmission.
You have two symptoms that are pointing to the same problem. Both your speedometer, and your transmission, use the VSS (vehicle speed sensor). The transmission uses the data to calculate shift points. If there is not any output, the computer will think you are not moving and not command the transmission to up-shift. The same sensor data is sent to the instrument cluster for the speedometer. The speed sensor is the most likely problem and will need replaced. Their are other possibilities like wiring, or a computer malfunction, but it is less likely. Their should be a code stored in the computer for this failure, but not always. If you would like this repaired, consider YourMechanic. We can provide a diagnostic of the issue with your gears and repair at your home or office.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing