Huh, iduno. Sounds like wiring IMO. Have you scanned it ? I'd scan it first with or without a CEL. Then run the wiring down, check the CHT harness. Yea, seems like you should be getting a CEL. It's also possible that you have two different problems going on. As said, the regulator can screw up a warm start, so can the MAF. Could also be the IAC. But, -I would want to know what's up with the cluster gauge as well. Not much help for yuh, but you have to start somewhere. Keep looking you'll find it.