HCz28

I have a2002 z28 with the ls1engine. After driving in heavy traffic the tempgauge gets up to 210degrees. When i stop and shut off the engine it will not start for about 5 minutes. There are no codes in the computor. Under normal running conditions the temp is 195to200 and there is no problem starting any ideas on what might be the problem

Injuneer

210*F is midpoint on the gauge, and that is the temperature GM designed the engine to run at. Have you gone to a lower temp thermostat?

Something would appear to be heat soaking. I gather from your other question that you suspect the CKP or CMP sensors. If those were faulty, even intermittently, they should set codes.

Just a wild guess, but if you hold the accel pedal on the floor before you turn the key to "start" and hold it there while cranking the starter, until the engine starts, will it start more quickly?