Starting problems 2002 boxter
 

Started having trouble with starting the car. Wait 15-20 minutes and then it starts. Very random. Took car to mechanic, changed air filter, replaced fuel pump. two weeks later back to where I started. Could it be electrical? Bad fuel pump replacement?

Do you have or have you gotten a CEL?
Does it happen right after fill up?
only when cold?
only when hot?
you say it is very random, but you also say you wait 15-20 minutes then it starts.
You wait 15-20 minutes after doing what??
how many miles on the car?
any mods?
Any work done on the car before the issue started?
The more info we have the better chance of helping;)

Does the tach move while cranking and not starting. Possibly the crank position sensor?

Will it start if you give it a little gas?