99 chev starting problem

i have a 99 silveraldo with a throttle body injection i was told that in 99 they went to different system may have early model,anyhow when it is cold it wont start after turning key of and on 5 or 6 times it will start runs fine once it is started starts fine rest of day

ok, you say turning the key on and off 5 or 6 times, so i want to be clear about what you're saying..... you say it wont start - when you say that, are you saying when it's cold, it wont turn over at all, or does it crank but not fire up? if it turns over but doesn't fire up, i'd check the temp sensor. if it doesn't turn over at all until turning it on and off 5 or 6 times, then here's a way you can help diagnose the problem. when the vehicle is cold first thing in the morning, using a voltmeter, test & write down the voltage. regardless of reading, connect a battery charger to it & wait for 1 minute. after 1 minute, turn the key & see if it will start. if it does start, & your voltage reading was 12.4 or more, then you probably have a weak or worn starter solenoid. when they're weak, they will not push the plunger quite far enough to engage power to the starter motor, so nothing will seem to happen. when you hook up a battery charger though, you push the voltage up just enough to make it engage (i've seen this on at least 20+ gm's). if your voltage was less than 12.4, then your battery is probably getting a bit aged or has a cell dying.