My Discovery 2 decided to dump all of the coolant from the system in the Walmart parking lot upon starting it on a nice 20°F day. I only found out when just down the road it started overheating bad. It took a while but I finally got it home after repeatedly stopping to let it cool off for a while and going again. This land rover also had an issue with the ground connection on the battery so after repeatedly stopping and starting, the battery ran dead as I got it home. I replaced the ground cable, the battery, and added coolant and it started up just fine. I took it out for a drive and everything went fine so I took it home and parked it. When I tried to start it again a few days later it cranked strong but didn't start. From what I read there was a good chance the crankshaft position sensor could have been damaged from the heat so I bought an oem replacement and installed it. This did nothing for the issue. It still cranks but won't start. My scanner showed a code P1668. I cleared the code but this also didn't resolve the issue. Does anyone know what could be causing my issues and how I could fix it?