2000 Silverado 5.3L w/ 130,000 miles on it takes several tries for it to finally start in cold weather (less than 32 degrees F). I've tested the ECT sensor for resistance and it checks out, but I'm thinking of having the truck scanned to double-check that the default setting of that sensor is correct.....I'm really grabbing at straws as I've tried everything....the cold start is the only issue. Once it's running, runs perfect w/ no misses and can restart w/ no problem. Seems like ambient air temp/engine block temp is the key issue. Folks have suggested cam or crank sensor, but I don't believe it as it's only cold temps when it's a problem.

So far I've replaced Fuel Pump, Fuel Pressure Regulator, Spark Plugs (iridium), Sprayed ether around intake gasket and found no leak, Battery checks out, MAF cleaned, Ether in throttle body during cold start makes no difference.