2005 chevy avalanche turns over alot before it starts most of the time and sometimes it starts fine

The 2005 Chevy Avalanche is available with different transmission and shift options, which can affect the number of transmission shift solenoids present.

However, generally, the 4-speed automatic transmission (4L60E) used in the 2005 Chevy Avalanche typically has a total of 7 transmission shift solenoids. These solenoids are used to control the activation and deactivation of the transmission's clutches and valves, allowing the vehicle to shift gears smoothly and seamlessly.

It's important to note that the number of transmission shift solenoids may vary depending on the year, model, and configuration of the Chevy Avalanche.
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You need to start this when it's cool not hot take your radiator cap off start the engine start adding water into the radiator keep checking it with your finger and keep adding when the water turns warm to the touch keep adding water if it's taking it and squeeze your upper radiator hose continuously to burp out the air keep adding water try that and see how it works

seems like your alternator might be the problem.

http://www.ehow.com/how_5730586_replace-chevrolet-avalanche-alternator.html

Were is the radio ground wire located on my 05 avalanche? Radio goes in and out all the time.

Check fuel pump relay under hood and fuse.If they are good it is going to be the fuel pump.

Could be your coolant temperature sensor is faulty,here's a link on how to replace.

The check valve in your fuel pump has failed. You need a new fuel pump. Try cycling the key a few times from off to on before trying to start to verify this. If it starts right afetr afetr a couple of off to on cycles then you know you need a fuel pump because it isnt holding pressure after you turn the car off.

Motor switch has gone out, most likely due to high load on level 5. Replace switch and I suggest lubricating blower motor bearing to help take the strain on the system.

Clean your throttle body and maybe even your mass air flow (if you use a K&N filter).

the timing is factory set no need to adjust