Idle Fix?
KK, it doesnt sound like its too serious really...just a:
mmmmmmmmbrpmmmmmmmbrpmmmbrpmmmmmmbrpmmmmmm
Text is limiting of course. Its like a slight 'shudder' when idling. I usually get it mainly in the mornings when I start her up. I have a garage so its not out in the elements.
mmmmmmmmbrpmmmmmmmbrpmmmbrpmmmmmmbrpmmmmmm
Text is limiting of course. Its like a slight 'shudder' when idling. I usually get it mainly in the mornings when I start her up. I have a garage so its not out in the elements.
Evolved Member
iTrader: (20)
Joined: Mar 2003
Posts: 4,941
Likes: 0
From: Danville/Blackhawk, California
There's a quick fix you can do yourself to eliminate the idle instability during open loop (cold start and such). Go to your MAF table and try putting "30" the bottom left cell (where idle occurs). This raises the tiny tiny MAF signal by 30% which is enough to push it just over the brink at which the engine runs. In fact, go ahead and apply this tweak between 0 and 3000rpm. Between 3000rpm and 5000rpm, taper the MAF adjustment down to 0 gradually so that no weird transitions occur.
This change will not make your car run noticeably richer at idle or degrade fuel economy or have any such side effects. Give it a shot and see how it behaves the next morning during cold start.
cheers,
shiv
This change will not make your car run noticeably richer at idle or degrade fuel economy or have any such side effects. Give it a shot and see how it behaves the next morning during cold start.
cheers,
shiv
Evolved Member
Joined: May 2002
Posts: 504
Likes: 0
From: Seattle, WA
Originally posted by vr430
Are you guys talking about "dieseling" when you shut the engine off? Is that normal? Mine is pretty bad and I am still stock...
Are you guys talking about "dieseling" when you shut the engine off? Is that normal? Mine is pretty bad and I am still stock...
As for idling issues, mine actually seems to be significantly smoother since installing my Xede.
Evolving Member
Joined: Apr 2003
Posts: 218
Likes: 0
From: Portland, OR
Originally posted by shiv@vishnu
There's a quick fix you can do yourself to eliminate the idle instability during open loop (cold start and such). Go to your MAF table and try putting "30" the bottom left cell (where idle occurs). This raises the tiny tiny MAF signal by 30% which is enough to push it just over the brink at which the engine runs. In fact, go ahead and apply this tweak between 0 and 3000rpm. Between 3000rpm and 5000rpm, taper the MAF adjustment down to 0 gradually so that no weird transitions occur.
This change will not make your car run noticeably richer at idle or degrade fuel economy or have any such side effects. Give it a shot and see how it behaves the next morning during cold start.
cheers,
shiv
There's a quick fix you can do yourself to eliminate the idle instability during open loop (cold start and such). Go to your MAF table and try putting "30" the bottom left cell (where idle occurs). This raises the tiny tiny MAF signal by 30% which is enough to push it just over the brink at which the engine runs. In fact, go ahead and apply this tweak between 0 and 3000rpm. Between 3000rpm and 5000rpm, taper the MAF adjustment down to 0 gradually so that no weird transitions occur.
This change will not make your car run noticeably richer at idle or degrade fuel economy or have any such side effects. Give it a shot and see how it behaves the next morning during cold start.
cheers,
shiv
Has anyone tried this (besides you Shiv)? Just curious.
Originally posted by Liandrin11
That's very odd! Your car diesels after shutting down??? That's not normal at ALL. What octane gas are you running?
As for idling issues, mine actually seems to be significantly smoother since installing my Xede.
That's very odd! Your car diesels after shutting down??? That's not normal at ALL. What octane gas are you running?
As for idling issues, mine actually seems to be significantly smoother since installing my Xede.
I tried it. It did help but it is still not as smooth as stock (is it supposed to be?). Before the fix it would "mmmmmmmmbrpmmmmmmm" when I gave it gas slowly between 1k and 3k RPM (not the whole way up by the way). Now it doesn't do it there but idle (900 - 1k) is still "bumpy". I haven't tried putting back the old map yet to see the difference.
Evolved Member
iTrader: (20)
Joined: Mar 2003
Posts: 4,941
Likes: 0
From: Danville/Blackhawk, California
Originally posted by vr430
Oh, oh. It happens EVERY time, regardless whether the car has been driven a short distnace or not. I run 91 octane.
Oh, oh. It happens EVERY time, regardless whether the car has been driven a short distnace or not. I run 91 octane.
Shiv
Evolving Member
Joined: Jul 2003
Posts: 169
Likes: 0
From: Atlanta, GA
Originally posted by shiv@vishnu
The idle fix is basically done. Only problem is that it totally changes MAF scaling so that the baseline maps (and custom tuned maps from dyno days) will no longer be appropriate. The software engineer is working on a few version of the firmware update that will not induce any rescaling of the MAF. You'll here it here first as soon as its done.
shiv
The idle fix is basically done. Only problem is that it totally changes MAF scaling so that the baseline maps (and custom tuned maps from dyno days) will no longer be appropriate. The software engineer is working on a few version of the firmware update that will not induce any rescaling of the MAF. You'll here it here first as soon as its done.
shiv
Originally posted by shiv@vishnu
Could you elaborate on this dieseling issue? Gasoline burning cars shouldn't do that. I'd recommend listening to another EVO to see if what you are hearing is normal or abnormal.
Shiv
Could you elaborate on this dieseling issue? Gasoline burning cars shouldn't do that. I'd recommend listening to another EVO to see if what you are hearing is normal or abnormal.
Shiv
