EvolutionM - Mitsubishi Lancer and Lancer Evolution Community

Notices
Evo Engine / Turbo / Drivetrain Everything from engine management to the best clutch and flywheel.

could somone explain something for me?

Thread Tools
 
Search this Thread
 
Old Apr 30, 2009, 05:25 PM
  #1  
Evolved Member
Thread Starter
iTrader: (37)
 
ch53avitech's Avatar
 
Join Date: Feb 2008
Location: San Diego, CA
Posts: 957
Likes: 0
Received 0 Likes on 0 Posts
could somone explain something for me?
My car is dyno tuned and ECU flashed and my mods are in my signature. Everytime I disconnect my battery, reattach it, and go to start my car, it won't idle. I start it and it just dies. Everytime. I have to have my foot on the gas the entire time I drive, even when stopped. It's usually fine by the next day.

I know when I disconnect my battery my ECU loses the flash and it has to go through hot-cold cycles to "relearn". This is what my friend tells me. I'm really not sure whats going on.

Could someone further explain this to me?

Is there something I can do so I can disconnect my battery without losing my tune?
ch53avitech is offline  
Reply Like
Old Apr 30, 2009, 05:27 PM
  #2  
Evolved Member
iTrader: (6)
 
btownsoccer22's Avatar
 
Join Date: Apr 2008
Location: Indiana
Posts: 1,004
Likes: 0
Received 0 Likes on 0 Posts
Your not "losing" your tune, it just has to re-learn it. No other way around it.
btownsoccer22 is offline  
Reply Like
Old Apr 30, 2009, 05:31 PM
  #3  
Evolved Member
iTrader: (26)
 
bluebanana23's Avatar
 
Join Date: May 2004
Location: DTX
Posts: 2,032
Likes: 0
Received 1 Like on 1 Post
My car does the same thing but always catches itself a split second before it dies. Dynoflash AL told me the ecu is looking for the throttle sensor or something like that. After driving 10 city miles, it's fine.
bluebanana23 is offline  
Reply Like
Old Apr 30, 2009, 05:36 PM
  #4  
Evolved Member
Thread Starter
iTrader: (37)
 
ch53avitech's Avatar
 
Join Date: Feb 2008
Location: San Diego, CA
Posts: 957
Likes: 0
Received 0 Likes on 0 Posts
Thanks for the explanations, I would love to hear more.

Also, whats the best way to get the car back to normal?
ch53avitech is offline  
Reply Like
Old Apr 30, 2009, 05:36 PM
  #5  
Evolving Member
iTrader: (1)
 
jroller's Avatar
 
Join Date: May 2006
Location: San Diego
Posts: 334
Likes: 0
Received 0 Likes on 0 Posts
That doesnt sound right. Ive had 3 different tunes via email and one 12 hours total of recent dyno time and my **** has never done that when the battery was disconected.
jroller is offline  
Reply Like
Old Apr 30, 2009, 05:55 PM
  #6  
Evolved Member
iTrader: (15)
 
rcheung's Avatar
 
Join Date: Oct 2004
Location: East Coast
Posts: 2,203
Likes: 0
Received 1 Like on 1 Post
This is a very common occurence. It happened to me as well when I had to unplug the battery to do some work . The first couple of starts it dies right away but is will eventually learn. Times vary on how long they take. It also affects the AC. If you turn the AC on and step on the clutch while the car is moving the RPMS will drop almost down to zero. The AC however takes alot longer to learn than idle.
rcheung is offline  
Reply Like
Old Apr 30, 2009, 06:01 PM
  #7  
Account Disabled
iTrader: (465)
 
TTP Engineering's Avatar
 
Join Date: May 2005
Location: Central FL
Posts: 8,824
Likes: 0
Received 2 Likes on 2 Posts
Relearning fuel trims. That is all. Has nothing to do with the ECU tuning. It is a closed loop function.
TTP Engineering is offline  
Reply Like

Trending Topics

Old Apr 30, 2009, 06:07 PM
  #8  
Evolved Member
Thread Starter
iTrader: (37)
 
ch53avitech's Avatar
 
Join Date: Feb 2008
Location: San Diego, CA
Posts: 957
Likes: 0
Received 0 Likes on 0 Posts
What are you supposed to do to get the car back to normal?
ch53avitech is offline  
Reply Like
Old Apr 30, 2009, 06:08 PM
  #9  
Account Disabled
iTrader: (465)
 
TTP Engineering's Avatar
 
Join Date: May 2005
Location: Central FL
Posts: 8,824
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by ch53avitech
What are you supposed to do to get the car back to normal?
Drive it.
TTP Engineering is offline  
Reply Like
Old Apr 30, 2009, 06:08 PM
  #10  
Evolved Member
Thread Starter
iTrader: (37)
 
ch53avitech's Avatar
 
Join Date: Feb 2008
Location: San Diego, CA
Posts: 957
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by TTP Engineering
Relearning fuel trims. That is all. Has nothing to do with the ECU tuning. It is a closed loop function.
Is there something to be done to prevent this?
ch53avitech is offline  
Reply Like
Old Apr 30, 2009, 06:14 PM
  #11  
Account Disabled
iTrader: (465)
 
TTP Engineering's Avatar
 
Join Date: May 2005
Location: Central FL
Posts: 8,824
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by ch53avitech
Is there something to be done to prevent this?
Stop disconnecting your battery.
TTP Engineering is offline  
Reply Like
Old Apr 30, 2009, 06:18 PM
  #12  
Evolved Member
iTrader: (22)
 
EvolNinja's Avatar
 
Join Date: Nov 2007
Location: Wisconsin
Posts: 1,638
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by jroller
That doesnt sound right. Ive had 3 different tunes via email and one 12 hours total of recent dyno time and my **** has never done that when the battery was disconected.
+1
To get the car back to normal, just reflash it back to your OEM rom. That should solve your problem. GL
Last edited by EvolNinja; Apr 30, 2009 at 06:29 PM.
EvolNinja is offline  
Reply Like
Old Apr 30, 2009, 06:25 PM
  #13  
Account Disabled
iTrader: (465)
 
TTP Engineering's Avatar
 
Join Date: May 2005
Location: Central FL
Posts: 8,824
Likes: 0
Received 2 Likes on 2 Posts
This is not the place for sales pitches. He appears to make decent power in his signature and fuel trim learning has nothing to do with the tuning of the vehicle.

Getting the car reflashed will solve nothing.
TTP Engineering is offline  
Reply Like
Old Apr 30, 2009, 06:35 PM
  #14  
Evolved Member
Thread Starter
iTrader: (37)
 
ch53avitech's Avatar
 
Join Date: Feb 2008
Location: San Diego, CA
Posts: 957
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by TTP Engineering
Stop disconnecting your battery.
Interesting.
ch53avitech is offline  
Reply Like
Old Apr 30, 2009, 06:48 PM
  #15  
Evolved Member
iTrader: (23)
 
PVD04's Avatar
 
Join Date: Jun 2004
Location: Wisconsin
Posts: 1,503
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by ch53avitech
Is there something to be done to prevent this?
Some people may disagree, but a better tune would help. WOT tuning may be fine, but if your car can't even maintain a rough idle after the battery is disconnected your tune needs work. The ECU shouldn't have to learn that much.
PVD04 is offline  
Reply Like



Advanced Search
Quick Reply: could somone explain something for me?


Reply Closed Thread Share

All times are GMT -7. The time now is 03:31 PM.