Ignition/Start Up Issue
 

Before I start, I moved from Florida to Colorado (didn't drive the brz). Mentioning this in case this problem is due to Hard cold starts and/or the 5w 30 motul I'm on.

In the last 2 weeks or so, I have encountered two issues on start up.

-About 5-7 times in those weeks, when starting the car, The RPM needle went straight to the engine's actual RPM. What I mean by this is that it did not touch the MAX RPM, come back down to 0, and then go to the Engine's actual RPM (normally what it does)

- The other issue only happened once. In startup it seemed the engine almost didn't start. It started just fine on the first try but there was a delay in the end. On ignition it the RPM needle went all the way up and almost down to 0 before the engine BARELY started.

Could this be Spark Plugs? Starter?

After these issues the engine still turns on just fine and it still runs good. Not a permanent issue but I don't want to let it get there.

Hmmm....... it could be:

* your car is just acting different (to you) because of the cooler temperatures and/or thinner air.

* the battery is not used to turning over a colder engine with heavier oil.

I suggest you have the battery checked out by having it load tested.


humfrz

Would the RPM needle be a battery-related issue?

I don't know, however if the battery will eventually start the car, it surely would have enough ump to make the needle jump.

I've never noticed what the tachometer needle does on startup on my 2013 FR-S ...... :iono:


humfrz

Have you reset the ECU since you moved into the mountains? Disconnect the negative battery cable, pump the brakes a few times and let it sit for 5 minutes. Reconnect the negative cable, start the car and let it idle for 10 minutes without touching anything.

I have not reset the ECU, I have only flashed a revision from my tuner. What are all those steps doing?

I thought that the ECU would be smart enough to automatically adjust to temperature and altitude differences ....... :iono:

If I'm misinformed, please straighten me out ..... :)


humfrz

The steps will clear everything the ECU has "learned" about it's environment and the corresponding tuning values (STFT, LTFT, etc). It will then re-learn based on the new altitude you're driving in now. Your tune should be fine as I believe it's loaded as a ROM into the ECU. Someone with more tuning experience would be able to verify, but my '01 RS that had a tune never lost it after resetting the ECU via this process.

How long have you been in CO?

It could very well be, but it could also take a while to straighten out the values. It would be dependent on how quickly the car can "learn" based on the higher elevations. This approach is a short cut to waiting for the ECU to re-learn.

I've been in Colorado around 25 days. First week I driving without a Revision (Still tuned at Sea Level)... Then I got the revision on the second weekend.
It is a ROM file on the ECU. Fuel trims are now on the negative side than what they used to be. I'm just not so sure these events are tune-related.