Q: Will a faulty crank position sensor affect my auto trans function? 2003 Dodge Grand Caravan

Hello - No, the crankshaft position sensor will not affect your transmission at all - except when it fails, and the engine ceases to run. Check your transmission fluid for the correct level and condition (pinkish, with no burned smell). If your transmission fluid has not been changed in recent history, it might be worth having a transmission fluid & filter service. It is also possible that your transmission is actually in 2nd gear and in "Limp Mode", which is what is does when there is an internal transmission failure. In your case, failure of an internal speed sensor in the transmission is a good possibility. I recommend a transmission inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

A faulty crankshaft sensor is also used by the transmission as an input shaft speed sensor for the transmission to shift correctly. The sensor may affect shifting and also the way the engine runs. Your engine may also have went into failure mode if the crankshaft sensor is failing. I would recommend repairing the sensor first to see if the transmission is being affected or it is having another problem.