Im working on a 2003 caddy cts with the 3.2lt. The engine stalls at times, mostly when it is hot. Sets codes for the crank sensor and cam sensor. Fuel pressure looks good even at stall. Someone has already installed an aftermarket crank sensor. Have you seen any issues with aftermarkt sensors? Any other ideas?

If the PCM is pointing at a crank sensor and the car is stalling, then I'd say this after-market sensor is no good. Replace it with an OEM part.