Big lean problem after switching to 2001 OS
Thread Starter
On The Tree
Joined: Dec 2005
Posts: 151
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From: South Dakota
Big lean problem after switching to 2001 OS I just recently switched to a 2001 OS and I am having issues with going lean during a shift. The car idles fine, drives at part throttle fine. But whenever I shift from 2nd to 3rd or 3rd to 4th, the TPS goes to 0% (because I let off), then the spark advance goes to -2 and then AFR goes to max (19.7). It then comes back a few seconds later. It doesn't seem to do it less then 20mph but any higher then that and it does that. Another thing I noticed was the injectors dropping from 9% duty to .5% duty. The RPMs also drop very very fast when I push the clutch in.
My ideas so far is that it had something to do with the Throttle follower and cracker tables but that doesn't seem to be it. Any help would be appriciated. I can get logs posted of the graphs if someone needs.
My ideas so far is that it had something to do with the Throttle follower and cracker tables but that doesn't seem to be it. Any help would be appriciated. I can get logs posted of the graphs if someone needs.
Thread Starter
On The Tree
Joined: Dec 2005
Posts: 151
Likes: 0
From: South Dakota
I thought it was DFCO too but I double checked that it is already disabled. I think I figured it out last night, it was the throttle follower tables for both in gear and P/N. They turned out to be 3 times higher then what my stock 2000 tune had. No idea why but it seems to have worked so far. I don't quite understand how throttle follower could cause more then 20 degrees of timing to be pulled.
Fuel cut and spark cut together is the signature of DFCO.
May want to "double kill it" or something (put the enable
values out of range etc.) just to be sure.
If you drop to TPS=0 then you are probably falling out of
PE (enable TPS, enable MAP) but that should only put you
back to closed loop, not this "decel lean mode". The fuel
trim cell # and commanded fuel air multiplier ought to tell
you more about what's going on in its mind.
May want to "double kill it" or something (put the enable
values out of range etc.) just to be sure.
If you drop to TPS=0 then you are probably falling out of
PE (enable TPS, enable MAP) but that should only put you
back to closed loop, not this "decel lean mode". The fuel
trim cell # and commanded fuel air multiplier ought to tell
you more about what's going on in its mind.
Thread Starter
On The Tree
Joined: Dec 2005
Posts: 151
Likes: 0
From: South Dakota
I have LTFT disabled and forced it into open loop right now. (No MAF) Does DFCO or the throttle follower cause the rpms to fall faster when you push the clutch in? Like the opposite of what I have would be hanging rpms inbetween shifts. Do our PCMs even have that ability, I realize the tables are there but does it even exist? Same with lean cruise. Sorry if there too many questions but I am far from understanding tuning.
Thread Starter
On The Tree
Joined: Dec 2005
Posts: 151
Likes: 0
From: South Dakota
Well, update again. I thought I had fixed it but it still does the same thing. DFCO is set to enable at like 410kph so thats not it. RPMs still drop inbetween shifts really fast and AFR goes up to ~18.5 now. Also, when coming to a stop, rpms will hold very steady at 1200 with AC on until the car hits 0mph. Even at 1mph the rpms will hold up at 1200.
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In EFI Live, it's called DFCO M6. From the factory, it'll enable during shifts as long as ECT is greater than 122*F, RPMs are greater than 900, MAP is below 104.98kPa, TPS is less than 8%, and you're going faster than 28 MPH.
I think that's everything.
I think that's everything.
DFCO M6 factory setting is changed from 2000 to 2001 - in 2000 it's disabled by the enable temp being set at 140 C, for 2001-02 the enable temp is 50. I found this when I upgraded my OS from 2000 to 02 - it acted a lot different between shifts, rpm went down very fast. I set the temp back to 140, due to also having the lean spot problem, but not sure it made any difference since I'm still getting pinging in low rpm range after shifting. (I had to deinstall my wideband a while back so don't know the actual afr.)