Hello, it is true, if you cannot get the problem to happen in a setting where a technician is testing it, you won't be able to determine the cause. Possible causes would be intermittent concerns with the transmission range sensor that sends information about the shift lever being in park or neutral positions. The brake lights switch not showing brake engagement could prevent starting. A starter, battery, or cabling issue could be a problem. The ignition switch could be suspect.
If you open your window and listen, do you hear a ‘tick’ from the engine bay each time you try your key? This could mean a faulty starter. Trying it a few times moves the position of the starter enough that you’ll eventually find a position that works. You can keep using it like this, but the problem will likely just continue to get worse.
If you turn the key and it tries to start the engine, but it doesn’t ‘catch’; it could be an immobilizer issue. Check your dash next time you start your car for a little car shaped icon with a key in it (near the top left of the dash lights i believe). If you see that icon, it means the immobilizer is recognizing an authorized key. If you don’t see that icon, then the immobilizer is actually “immobilizing” your car and not letting it start. So the problem could be the chip in your key (try a different key) or the sensor in the key hole.
For me - I had the immobilizer issue, but my problem was further complicated by a remote starter system that ‘bypassed’ the immobilizer causing other issues. Now I unplug the remote start system anytime it acts up and I’m never left stranded!
