Induced MAF failure = shifting out of park HARD on cold starts?
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Induced MAF failure = shifting out of park HARD on cold starts?
I'm trying to tune my VE's and the entire time doing this, I am getting HARD shifts from a cold start from P to Drive or Reverse.
Like everytime I have to consciously consider if I am applying enough brake pressure to compensate.
Warm starts are fine though.
I can't seem to grasp why this would be happening.
I understand that the computer is using a less accurate fueling table (secondary VE) in this mode, but I havn't modified any shift properties in the transmission settings yet.
I suppose it could have something to do with Idle airflow ..maybe?
Does anyone have any thoughts or ideas?
Any help appreciated.
DJ
Like everytime I have to consciously consider if I am applying enough brake pressure to compensate.
Warm starts are fine though.
I can't seem to grasp why this would be happening.
I understand that the computer is using a less accurate fueling table (secondary VE) in this mode, but I havn't modified any shift properties in the transmission settings yet.
I suppose it could have something to do with Idle airflow ..maybe?
Does anyone have any thoughts or ideas?
Any help appreciated.
DJ
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John, some cars command max line pressure when the MAF is not working. I would recommend e-mailing HPTuners support if its going to take you a while to tune your VE. They may have you e-mail them your bin so they can keep it from commanding max line pressure like that.
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Originally Posted by SMOKINV8
John, some cars command max line pressure when the MAF is not working. I would recommend e-mailing HPTuners support if its going to take you a while to tune your VE. They may have you e-mail them your bin so they can keep it from commanding max line pressure like that.
Just posting for any other searchings sake.
In the 2000 OS, there IS a switch that does just that.
It commands full transmission line pressure when P0101, P0102, or P0103 errors are set.
There is a switch to shut it off though, which I stumbled on trying to convert to 2001..
I flipped these 3 switches to disabled, and it shifts like a dream now.
This was nice to find, as I heard running like that can burn out a tranny pump.
Sorry to bump, but in case others have the same problem, they may stumble on this with a search.
DJ
Last edited by DirtyJohn; 07-04-2006 at 11:49 PM.