[SpriteKit Swift]Trying to spawn cars and move them down the screen at a pace that varies - swift

Question

So, I am making an app for my friend and I need to make cars spawn in 1 of 3 lanes on a road randomly, then move down the screen at a pace that can and will vary at multiple points during the car's lifetime.
let createCarAction = SKAction.runBlock({ //Creates the cars every 4 seconds w/ a waitAction
let laneNum = laneList[Int(arc4random_uniform(3))] //There is an array higher up with the X values of each lane that the cars can use
let newCar: SKSpriteNode
let num = arc4random_uniform(4) //picks random car color
if num == 0 {
newCar = SKSpriteNode(imageNamed: "Audi")
} else if num == 1 {
newCar = SKSpriteNode(imageNamed: "Audi2")
} else if num == 2 {
newCar = SKSpriteNode(imageNamed: "Audi3")
} else {
newCar = SKSpriteNode(imageNamed: "Audi4")
}
newCar.xScale = 0.30
newCar.yScale = 0.30
newCar.position = CGPoint(x: laneNum, y: CGRectGetMaxY(self.frame) + newCar.size.height/2) //puts the car in the picked lane and just above the screen
newCar.zPosition = CGFloat(2)
self.addChild(newCar)
let carAction = SKAction.runBlock({ //this is where it starts going bad. This action is run so many times in the first second the scene starts that it does not switch transition from the scene before it.
if newCar.position.y > (CGRectGetMinY(self.frame)-newCar.size.height) { //if the car is on the screen basically
newCar.position = CGPoint(x: newCar.position.x, y: newCar.position.y-CGFloat(spd))
print("test")
} else { // not on the screen
newCar.removeFromParent()
print("car y: \(CGRectGetMaxY(self.frame) + newCar.size.height/2)")
newCar.removeAllActions() // This does not seem to have any affect as when only one car has been created, carAction is still running seconds after the car has left the screen
}
})
newCar.runAction(SKAction.repeatActionForever(carAction))
self.newCarList.append(newCar)
print("made new car")
})
I have the spawning working, but when newCar.runAction(SKAction.repeatActionForever(carAction)) comes into play, the app does not move to the GameScene from the MenuScene. I think that the car just instantly moves to the bottom, then the game just lags out trying to print where the car is. I have the road moving in the update function.
override func update(currentTime: CFTimeInterval) {
/* Called before each frame is rendered */
if road1.position.y > CGRectGetMinY(self.frame) {
road1.position = CGPoint(x: CGRectGetMidX(self.frame), y: road1.position.y - CGFloat(spd)/2)
road2.position = CGPoint(x: road1.position.x, y: road1.position.y + road1.size.height)
} else {
road1.position = CGPoint(x: CGRectGetMidX(self.frame), y: CGRectGetMidY(self.frame))
road2.position = CGPoint(x: road1.position.x, y: road1.position.y + road1.size.height)
}
}
I can't think of a way to move the cars that doesn't involve a massive array or a complex SKAction that moves the car instantly instead of at the same pace as the road.
Thanks in advance.
Edit: Formatting

Answer 1

I ended up figuring out a way to use an SKAction.
let carWaitAction = SKAction.waitForDuration(1/60)
let carAction = SKAction.runBlock({
if newCar.position.y > (CGRectGetMinY(self.frame)-newCar.size.height) {
newCar.position = CGPoint(x: newCar.position.x, y: newCar.position.y-CGFloat(spd/3))
} else {
self.score = self.score+5
newCar.removeFromParent()
print("car removed")
newCar.removeAllActions()
print (newCar.hasActions())
}
})
newCar.runAction(SKAction.repeatActionForever(SKAction.group([carWaitAction, carAction])))