Notices
ECU Flash

Bad idle after flashing map

Old Oct 24, 2021 | 06:37 PM
  #1  
Tomkun's Avatar
Thread Starter
Newbie
 
Joined: Oct 2021
Posts: 13
Likes: 1
From: San Antonio
Bad idle after flashing map

Hey so I just purchased a evo 8 and I’ve been trying to learn the ecuflash software. I recently messed with the idle tables trying to lower my cold start idle but when I flashed the adjusted map my idle was fluctuating between 500-1000 and seem like it wanted to die but eventually steady out at 1100.

I decided to flash my original map to see if the probably was from my adjustment but i still had the same idle issue at start up.

I’m trying to figure out if flashing a new map erases the fuel trims and that’s why I’m having these issues, does it need to just relearn the fuel trims again?
Reply
Old Nov 14, 2021 | 03:41 AM
  #2  
carbon_toast's Avatar
Newbie
5 Year Member
 
Joined: Oct 2016
Posts: 58
Likes: 17
From: Colorado
Originally Posted by Tomkun
I’m trying to figure out if flashing a new map erases the fuel trims and that’s why I’m having these issues, does it need to just relearn the fuel trims again?
Reflashing on an Evo 8 will not reset the fuel trims. You will need to disconnect the battery for a moment to reset the trims.

Also, you say you recently purchased the car -- I would not assume that idle problems come only from the tune. These cars have likely gone through quite a few owners at this point. You should do a visual inspection, especially of the boost hoses and vacuum connections. Do a boost leak test if you can. Also check to see if your IACV is healthy. There are quite a few posts on the forum that you should seek out concerning aftermarket IAC valves that did not match the behavior of the OEM valve and caused idle issues.
Reply
Old Nov 15, 2021 | 04:21 PM
  #3  
hutch959's Avatar
Evolved Member
iTrader: (18)
 
Joined: Nov 2004
Posts: 1,459
Likes: 110
From: Chattanooga, TN
im no tuner... but i will say if i was a tuner, i would tell you to look at your logs and see what is going on... then make the changes to fix the problem

if you dont know what to look for in the logs, then playing with the tune is a dangerous game if your not sure what your doing.

i
Reply
Old Nov 16, 2021 | 06:28 PM
  #4  
Tomkun's Avatar
Thread Starter
Newbie
 
Joined: Oct 2021
Posts: 13
Likes: 1
From: San Antonio
Originally Posted by carbon_toast
Reflashing on an Evo 8 will not reset the fuel trims. You will need to disconnect the battery for a moment to reset the trims.

Also, you say you recently purchased the car -- I would not assume that idle problems come only from the tune. These cars have likely gone through quite a few owners at this point. You should do a visual inspection, especially of the boost hoses and vacuum connections. Do a boost leak test if you can. Also check to see if your IACV is healthy. There are quite a few posts on the forum that you should seek out concerning aftermarket IAC valves that did not match the behavior of the OEM valve and caused idle issues.
Thanks, I will do a boost leak test and go over everything to verify there’s no leak first.
Reply
Old Nov 16, 2021 | 06:31 PM
  #5  
Tomkun's Avatar
Thread Starter
Newbie
 
Joined: Oct 2021
Posts: 13
Likes: 1
From: San Antonio
Originally Posted by hutch959
im no tuner... but i will say if i was a tuner, i would tell you to look at your logs and see what is going on... then make the changes to fix the problem

if you dont know what to look for in the logs, then playing with the tune is a dangerous game if your not sure what your doing.

i
ecuflash is totally new to me but I got a chance to look at my tune and it’s hard to follow everyone’s advice on the forum since the tables are different depending on which version you have.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Derekhollister
Evo General
12
Oct 6, 2019 10:18 AM
06Black
ECU Flash
3
Feb 22, 2012 01:13 PM
xhomm02
Evo X Engine Management / Tuning Forums
9
Dec 8, 2011 01:04 AM
diiirk@AwdMotorsports
ECU Flash
6
Apr 17, 2008 07:44 PM
awdgsx91
ECU Flash
7
Oct 11, 2006 06:57 AM


Thread Tools
Search this Thread

All times are GMT -7. The time now is 03:48 AM.