One problem related to speed sensor has been reported for the 2009 Chevrolet Impala. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 Chevrolet Impala based on all problems reported for the 2009 Impala.
The traction control, stability track and abs lights all came on. The engine power reduced light came on and engine power was lower. I had the left speed sensor replaced and the accelerator sensor replace on August 8th after the dealership had fixed this problem in April and again in June. I was told they changed sensors then also, but I am not sure of which ones at that time. I am now having the same problem for the forth time. Replacing the sensors every few months is getting expensive. Also not very safe. I contacted gm and the woman told me to take it back to the dealership to be fixed again. I have fixed the same issue three times already. They were of no help at all.