Hey guys I need your advice on what this might be thats causing an issue

So far I have went thru two different alternators and 3 batteries and the issue still exists so I am not sure what could be causing this, but sometimes when I go out to start my car it will startup and idle at 900rpm as intended, and othertimes when I first start the car it will drop idle to about 400 rpms then after two or three seconds idle up to to 900rpms. Then there is the issue where it sometimes drops to 400rpms and the stalls while trying to climb back up to 900 rpms. When it does the climb and stall. My only way to start it is to actually apply some gas to quickly to raise the rpm's while trying the engine start. I know that some will say applying gas does not matter, but I can tell you if I try to start the car normally it will not start until I apply gas and revv up the rpm's once it has stalled out. I will even upload a video of this. Both trying to start it the normal way and then giving it some gas and watching it fire up. As I back out of the parking space and wait at the light I have to keep revving it for a bit or it will stall until the car has idled at 900rpm's long enough. The climb and stall typically happens when I have driven somewhere then I go inside and come back out. Its rare for it to do it on the first start of the day or if the car has been sitting awhile.

Now whats interesting is I can tell when the car is going to have an issue before I even start it just by trying the drivers side window controls which are unresponsive. If the window controls are unresponsive I get this rpm drop if the window controls function right before I even turn it over it will run perfect. It will also throw a service engine soon light as soon as I turn the steering wheel when pulling out of the driveway if the window controls do not work. If the car idles properly the windows work fine and the service engine soon light never comes on.

The car itself is modified and cammed so there has been some work done to it. It has a car audio system in it aswell as lastek led

Edit:
If you read my previous thread you would know that I have been having some strange issues with this car, but all of those past issues were resolved.
The old issue was due to a bad alternator and a broken plastic nipple on the coolant tank which caused the car to have no coolant. So when the car hit 220 degrees it wanted to stall.
The alternator and coolant tank were swapped for a new once and the car was re-tuned for all of the newly installed components. The tune lasted for about six months and the car ran perfect without any issues.
Then the car started to experience rpm drops on startup.

The tuner said that he had to fix a pcv line issue since this was causing a check engine light due to a vacuum leak before the car could be retuned. Would this cause a bad idle start if that issue came back and his fix did not work? As far as I know he did not replace it. He just repaired it so the car could be retuned.

I'll see if I can upload some videos to show you whats happening.

 

Your tuner doesn't know what he's doing or the idle would be fine. The voltage at startup is very important in my opinion. I have speculated that there is a sample and hold circuit in the PCM which set up a voltage threshold for all the sensors as the car runs. I speculate this because I replaced the starter in my 98 with an AC Delco starter and it resolved all my start-up problems where I would have to shut the car off and start it again for it to run correctly. It worked like that for 6 years without ever happening again.

But that doesn't excuse the person who did your tune. I tuned my own which had 600 lift and 12 degrees of overlap, 234 duration and mine idled relatively smooth at 700 RPMs.

 

And for the record, all I needed to do was read you saying the car is set to idle at nine hundred RPMs and that's all I needed to know about your tuner.