My car was sitting for a week in the cold and my battery finally crapped out. I purchased a new one and started the car up. It was running horribly and I could be mistaken about his but it felt like the car wasn't running on all cylinders. It almost sounded like a STI.

I have no check engine lights on. But this can be due to the car running on the HKS Fcon. Any ideas on what it might be?

ECU, throttle body, plugs, or coil pack perhaps?? Smells like it's running bad too.

 

What mods?

 

Is your ECU flashed?

 

jwt TT w/ built block and Fcon.

 

I believe it is but the flash would still stay though right?

 

Did you do the obvious and check your coil and plug connections? Also any connections up around the battery compartment you may have knocked loose.

 

Check for water on the ECU/harness.

 

also check your coil packs.

 

I'm going to do that today. I'm just panicking and hoping it's not something major I guess.

 

reset your tb after the car is fully warmed up.

 

The key is right there, has it been warmed up when your experiencing this? If so, then the tune is most likely still ok and it's a reset somewhere that must be done over. I had the same thing two years ago, reset the TB and TPS everything was fine. Just my $.02

 

I've had two times when my tune was not happy after a jump start. One of which, doing the ECU and throttle body reset cleared.

The other, you can see the results in this vid:

http://www.youtube.com/watch?v=UUiIWt6n2F8

That time, it was only cleared after I used the button sequence to change to another map and then change back. It's just something else that you can check.

 

Well I tried to do the reset but I couldn't do it. The CEL light doesn't shut off unless I start the car. Is it because the Fcon controls everything?

 

If you change a battery would it change the map on the Fcon?

I was also wondering if I would still see CELs still if the Fcon controls pretty much everything.

 

CEL is always on until the car starts.

 

you must have the car at operating temperature to properly do the TB reset.

do the foot pedal procedure. Hold the pedal down til the CEL stops blinking. Once it stops blinking you start the car.

 

the FCON just "steals" control over the injectors and coils, splices into sensors to share with the stock ECU, and sends an emulated MAF signal down the MAF input on the stock ECU so that it doesnt complain about the lack of a MAF or higher airflow if you left the MAF in.

So the CEL and everything still works as it always did.

You asked if it would "change the map" on an FCON to disconnect battery. I believe you are asking if the tune will stay saved in it, and the answer is yes. I have left my Z without a battery for winter storage and my FCON mapping was still there. But if I follow your question exactly as you asked it, will it change the map... I dont know because I never tried having multiple maps in my FCON... I believe that is a function of the Navigator when combined with the FCON because I never noticed or ran into that in the Power Writer software. Anyways what I am getting at is if you have multiple maps in your setup and you disconnect the battery, I have no idea if it will default back to the first map or what. So I suppose if you had two vastly different maps like one for gasoline and one for E85 and it switched on you, that could run very poorly depending on how aggressive you have the air/fuel feedback setup.

 

^ this. key ON engine OFF = CEL ON

 

No matter how many times I gave it a shot I just could t do the TB reset. I couldn't get it to do it.