What makes my 1996 Cad Seville SLS hard to start during below 40 degree temps besides battery problems.
Could be your air charge temp sensor reading wrong or engine coolant temp sensor also reading wrong, they might not set a code cause they are operating but just not correct specs relating to temps. The best way is to bring up the live data on the screen for those 2 sensors then check the chart for reference values depending or temperature.
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