Tuning question, please help..
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From: Houston (The Champions)
Whats meant by "desired air" my tuner guy was tweaking the tune on my turbo TA and was messing with the "Desired Air", now the car idles real high as I come to a stop, or when Im just driving if I push in the clutch my car revs up to like two grand.....
As defined by EFILive:
{B4307} Desired Airflow
Used to reduce airflow as the engine warms up.
Although listed in the "Idle" section, this calibration also controls the base airflow for non-idle conditions.
Log parameters (PIDS):
GM.IAC_LTD_DMA & GM.IAC_STD_DMA
and (A4)
GM.IAC_LTPN_DMA & GM.IAC_STPN_DMA
Then add the values of a calc.pid derived from those PIDS
The calc.pid is defined:
{GM.IAC_LTD_DMA} + {GM.IAC_STD_DMA} = X
and (A4)
{GM.IAC_LTPN_DMA} + {GM.IAC_STPN_DMA} = X
You might want to try raising your
Throttle Cracker Activate and Deactivate Speeds, that may help.
{B4307} Desired Airflow
Used to reduce airflow as the engine warms up.
Although listed in the "Idle" section, this calibration also controls the base airflow for non-idle conditions.
Log parameters (PIDS):
GM.IAC_LTD_DMA & GM.IAC_STD_DMA
and (A4)
GM.IAC_LTPN_DMA & GM.IAC_STPN_DMA
Then add the values of a calc.pid derived from those PIDS
The calc.pid is defined:
{GM.IAC_LTD_DMA} + {GM.IAC_STD_DMA} = X
and (A4)
{GM.IAC_LTPN_DMA} + {GM.IAC_STPN_DMA} = X
You might want to try raising your
Throttle Cracker Activate and Deactivate Speeds, that may help.
He probably raised it to help with the idle when the car is sitting still - but he needs to compensate with the throttle cracker table to bring your idle back to where it should be when the car is rolling...
Hey Charlie, man last night I was going thru my voice mails and heard one from you awhile back, sorry I missed it, There are throttle cracker tables and decay tables that sound like they need to be adjusted, also the IAC follower can be too high, there are a few items that need to be looked at.What does your tuner say? is he not sure......Beware, it only takes one wrong stroke of the key to go Boom!
Thread Starter
11 Second Club
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From: Houston (The Champions)
Well, Im going back Friday to get the turbo hard piped from the intake to the intercooler. He is gonna make some changes to the tune. Ive gotta get this right because Im taking this car to Washington State to be used as my daily driver for the next two years. Cant afford to have anything go wrong once Im there.
Hey where in Houston are you guys? I just moved down to Tx and I'm looking for some good guys to chill with. Sadly I can't help you with your problem. I am just starting to look into tuning my own car.
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Thread Starter
11 Second Club
iTrader: (6)
Joined: Dec 2003
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From: Houston (The Champions)
Welllllll come to find out the tune was dead on, apparently when I was getting on it leaving the shop last weep, the back pressure from the turbo blew off a loose vacuum line causing a HUGE vacuum leak. I put it back on and secured it real well and all good.



