I can reproduce the struggle-to-start issue
 

I don't know if this applies to the manual or the frs, but i have a BRZ limited auto, and i figured how to reproduce the struggle-to-start issue.

When starting the car with push button start, the process normally is: step on brake, push the button. I find if i don't step on the brake all the way down AND press then release the push start button right away, the car will struggle to start.

Here is what i tried on the same day:

First try in the morning: step on brake firmly, push start button hold for 1 sec, car starts fine.

Second try after the the first drive in the morning: step on the brake lightly, press the start button and release right away, car struggles to start, but eventually started.

I repeated the above the next day, same result. I tried these about a week ago and i have been firmly stepping on the brake and hold the push start for 1 sec and haven't had the car struggle since.

Not sure if it's just my car, or anyone with an auto with push start can reproduce this? Donno about the manual start procedure. Maybe some of you who are mechanically inclined can speculate what's wrong based on my steps?

hmm. I need to try this but I have been getting spotty starts as well.

security measures?
In the owner's manual, it is mentioned: "firmly depress the brake pedal" and continue until engine starts.

For Manual you have to press the clutch.

Yeah on a manual, if you release the clutch (while in neutral) during the starting procedure, it will kill the engine... I guess it's a question of timing that differentiates struggle-to-start and plain ol' stall.

Thanks potato.

I don't even think I press the brake when I start the car; just the clutch since my e brake is engaged.

Must remember to try this later.

So what you're saying is, when you don't follow the procedure properly as per the owners manual, it doesn't work properly? Seems pretty self-explanatory to me. We in the aircraft maintenance field call that "pilot error."

If a non-qualifying sequence is initiated, the vehicle shouldn't struggle to start: it should not try to start at all.

Pilots (even private ones like me) tend to call that "design flaw". :D

So in other words: If you don't allow the car to prime itself it will struggle to start.

In other news cars continue to operate as designed.

Fuel pump priming in a Limited must be done by pressing the start button twice with the clutch engaged (foot off pedal). Due to the five seconds longer this takes me, I don't do it. Never had a reproducible starting issue. Only inconsistent struggle to start occasionally when cold and several times after starting shortly after a drive.

The sequence OP is describing isn't wrong, just that he's not holding the brake firmly and, what I'm guessing the real issue is here, he's not holding the start button long enough. I've had my FR-S struggle to start a few times as well (which is how I found myself in this thread to begin with) but it was always when I was in a rush and let go of the key too soon. Usually it cranks through 3-4 firing sequences before fully coming to life, but for some reason sometimes it takes longer. Thought the reason for that was being addressed here, but when I read the thread I just had to laugh.

I don't think you need to press the brake while starting a manual car...

what i'm saying is, for those who are experiencing this issue, maybe they didn't press the brake HARD ENOUGH even if they thought they press the brake firmly. The word "firmly" is pretty subjective. We in the software field don't believe in subjective terms. We like to have everything to be "measurable". ;)

again, this reproducing sequence is my personal experience, and it's with the auto. YMMV.

Push start auto 100% does require the brake being depressed, if using my dad's Lexus as the basis...I'm certain smart key/push-start systems used are the same.

It's not a requirement for the manual either, but probably good practice.

oddly, yesterday my car wouldn't start and it took about 7 seconds of continuous nonstop cranking before it turned on... hello future engine problems?

i experienced it for the first time yesterday as well. push button start, auto transmission. i don't recall how firmly i was pressing on the brake pedal, but it took about twice as long as usual to crank before it started - maybe 5-6 seconds. this was in the afternoon, about an hour after i had driven it somewhere, so it wasn't a completely 'cold' start. never had a problem with cold start in the morning, or going home from work, when the engine has had time to cool completely in-between starts.

You know I had the same thing on my manual FR-S where it won struggle to start, happened maybe two times a week to me. When I was installing my Perrin silicone intake tube, for giggles I completely disconnected the battery terminals and ground and tightened everything back up nice and firm with a ratchet. Hasn't struggled to start since, and that was over six weeks ago in the same type of weather. I have a feeling flinging the car into a few select corners every day on the way to work probably loosened the connections causing the weak start. Maybe give that a try just to be on the sage side?

To add, I don't have to wait for anything to prime either after tightening up the connections, just turn the key immediately after putting it in and it starts right up.

Not sure why you would need to press the brake anyway to start an automatic. I assume these cars (as do all automatics except maybe cars that are antiques over 50 years old) have a 'Neutral Safety Switch' and the car will only crank when in Park or Neutral. Manual transmission cars have a 'Clutch Safety Switch' and will only crank when the clutch pedal is depressed. Are these cars any different? I'd think that pressing the brake pedal might only be a safety thing (since about half the owners manual seems to be safety bullets) that the manufacturer writes in there in the odd chance that your neutral safety switch fails and allows it to crank in reverse or drive.