Discovery I Talk about the Land Rover Discovery Series I within.

IDLE trouble

Thread Tools
 
Search this Thread
 
Old May 16, 2011 | 05:40 AM
  #1  
LRD2&ME's Avatar
Thread Starter
|
Winching
Joined: Apr 2011
Posts: 553
Likes: 8
From: Oklahoma; where the winds come rolling down the plains.
Default IDLE trouble

So this past weekend my LD1 developed a little hickup. When I started up Saturday morning my Idle went straight to 2000. I had to go somewhere so I drove it for about three miles like that. I shut it down, went to work, came back after about four hours and started it up. It started with very low RPM's and wanted to stall. I got it home and changed out the MAF. No, not the MAF. I went straight to the ECM and swapped it out with my extra. The RPM's are normal now and start up is normal. I opened the ECM but did not notice anything out of the normal. This thing has me wondering what happened. No maisture, no damage.
 
Reply
Old May 16, 2011 | 10:38 AM
  #2  
Jull's Avatar
Winching
Joined: Oct 2008
Posts: 572
Likes: 1
From: St-Lazare-de-Bellechasse
Default

My guess is that your issue was not related to the ECM. The adaptative memory of your new ECM is "learning" to work with a possibly bad sensor. It is possible the issue will be back sooner or later.
 
Reply
Old May 16, 2011 | 10:54 AM
  #3  
LRD2&ME's Avatar
Thread Starter
|
Winching
Joined: Apr 2011
Posts: 553
Likes: 8
From: Oklahoma; where the winds come rolling down the plains.
Default

Interesting; Do you know the time frame involved in learning the new adaptative constance.
 
Reply
Old May 16, 2011 | 11:45 AM
  #4  
turf63's Avatar
Recovery Vehicle
Joined: Feb 2010
Posts: 1,057
Likes: 23
From: Boston
Default

Similarly, not tryingto high jack but would the opposite learning "unlearning" take the same amount of time? Like if I were getting bad mpg's from bad o2 sensors would the ecu unlearn the air fuel mix the same way its going to learn lrdii&me's rough idle issues?
Back on topic I'd def agree that if it comes back it's a bum sensor and the ecus both work fine
 
Reply
Old May 16, 2011 | 06:03 PM
  #5  
LRD2&ME's Avatar
Thread Starter
|
Winching
Joined: Apr 2011
Posts: 553
Likes: 8
From: Oklahoma; where the winds come rolling down the plains.
Default

So today I wanted to see if this learning event would work on the ECU I removed. Nope; my RPM's went straight to the roof on startup. Tried cold and warm, same event. Pulled the ECU and dropped in my spare again. Clean, smooth idle. Interesting. Wondering what component in the ECU actually functions as memory, or does it go through a boot up process at each start? Opened the ECU and do not see any ROM/RAM type setup.
 

Last edited by LRD2&ME; May 16, 2011 at 06:06 PM.
Reply
Old May 16, 2011 | 07:09 PM
  #6  
turf63's Avatar
Recovery Vehicle
Joined: Feb 2010
Posts: 1,057
Likes: 23
From: Boston
Default

Hmmm. Idk. This is just something that has been relayed to me and I absorbed. But in my instance it was in regards to the o2 sensors and mpg's so idk if any of it learns or if only part of it learns.
 
Reply
Old May 16, 2011 | 07:35 PM
  #7  
Spike555's Avatar
Team Owner
Joined: Jun 2007
Posts: 26,212
Likes: 98
From: Grand Rapids MI
Default

Drive it with the "new" ecu and see if the issue comes back after a couple of weeks.
 
Reply
Old May 16, 2011 | 07:41 PM
  #8  
LRD2&ME's Avatar
Thread Starter
|
Winching
Joined: Apr 2011
Posts: 553
Likes: 8
From: Oklahoma; where the winds come rolling down the plains.
Default

Yeah, will do. I will be watching this one closely. Glad I didn't get rid of my extra ECU.
 
Reply
Old May 16, 2011 | 07:50 PM
  #9  
Spike555's Avatar
Team Owner
Joined: Jun 2007
Posts: 26,212
Likes: 98
From: Grand Rapids MI
Default

I wish I had a extra MAF and ECU...I have a extra water pump and alternator though.
 
Reply
Old May 16, 2011 | 08:11 PM
  #10  
Danny Lee 97 Disco's Avatar
Joined: Mar 2010
Posts: 5,584
Likes: 7
From: Pittsburgh PA suburbs.
Default

Spike do you still have the Parts Disco?
 
Reply



All times are GMT -5. The time now is 10:22 AM.