* Transmission Fluid: Low fluid level, contaminated fluid (burned, dirty), or fluid that's the wrong type can severely impact the transmission's ability to shift correctly. The viscosity changes significantly with temperature, and improper fluid exacerbates this issue. Cold, thick fluid may struggle to flow properly, preventing shifts.
* Valve Body Problems: The valve body contains numerous valves and passages that control fluid flow within the transmission. Worn or sticking valves, particularly those related to the shift solenoids or governor, can prevent the transmission from shifting out of first gear until the fluid warms and thins slightly, allowing them to function better. This is a common culprit in older automatic transmissions.
* Governor: The governor uses engine speed to determine shift points. A malfunctioning governor, which is often affected by the fluid condition, can cause the transmission to remain in first gear.
* Temperature Sensor: Some transmissions use a temperature sensor to adjust shift points. A faulty sensor providing incorrect temperature data could lead to the transmission staying in first gear until it reaches a certain temperature.
* Torque Converter Issues: While less likely to cause this specific symptom solely, problems with the torque converter's clutch or its internal components could contribute to poor shifting, especially when the fluid is cold and thick.
* Shift linkage (if applicable): Although less common with a completely electronic system, there may be some mechanical linkages that could be binding in the cold. This is less likely in the later models, but worth noting.
Troubleshooting Steps:
1. Check the transmission fluid: This is the first and most important step. Check the fluid level using the dipstick (with the engine running and at operating temperature), note the color and smell (burnt fluid smells acrid). If it's low, add the correct type of automatic transmission fluid specified for your Tempo's transmission. If it's dark, burnt, or smells bad, a complete fluid and filter change is necessary.
2. Consult a repair manual: A repair manual specific to your 1986 Ford Tempo will provide details on testing components like the governor, temperature sensor, and valve body.
3. Professional Diagnosis: Automatic transmission problems are complex, and attempting repairs without experience can worsen the situation. A professional mechanic specializing in automatic transmissions can properly diagnose the problem using specialized tools and equipment. They can perform tests to pinpoint the faulty component and provide accurate repairs.
Ignoring the problem will likely lead to more severe damage and higher repair costs. A functioning transmission is vital for safe driving.
