""With the physical connection removed between the accelerator pedal
and throttle blade, some redundancy and safety checks are now
required. The most obvious is the addition of a second TPS sensor. The
additional sensor uses either a different range or slope than the primary
TPS and is used to verify actual position as well as perform a rationality
check on the primary sensor output. Any errors between the two TPS
sensors usually lead to a fault code and possible trigger of a failsafe
mode.
The ETC strategy must also have some form of failsafe detection for
stuck open throttle or improper operation at part load. Since there are
no longer external springs mechanically forcing the cable to retract
when the driver lifts off of the accelerator pedal, great care must be
taken to make sure that the ETC’s stepper motor is under control at all
times. To prevent engine damage and reduce chances of a vehicle
crash, this failing condition triggers a “limp mode” for the ETC system
where the throttle position is limited to a very small value (usually less
than 20%) until reset. ETC systems usually have a table in the ECM of
maximum airflow rates at a commanded throttle position and engine
speed. (See Figure 5-4) If the airflow exceeds the table’s value, it is
determined that something must be wrong with the ETC hardware.
When parts are changed on an ETC equipped vehicle in the name of
adding horsepower, we run the risk of exceeding the PCM’s predicted
maximum airflow. It’s not unusual to see an ETC equipped car suddenly
drop into limp mode on the first test drive after adding a supercharger
or larger camshaft. This is due to the added airflow. The solution is to
reprogram the PCM to allow for higher airflow rates at high throttle
before triggering limp mode. A safety margin of roughly 20% should be
sufficient, but each vehicle can be unique. Only actual testing on the
specific combination of vehicle and performance parts dictates the
proper values to maintain safety without inadvertently triggering limp
mode under power. Again, great care must be taken not to simply
disable this function. This would leave the potential failure of a stuck
throttle and vehicle crash as the responsibility of the person who
modified the PCM. If the OEM doesn’t want to be taken to court, it’s
doubtful a smaller shop or individual tuner would fare well either.""



anybody met this question in tuning throttle ? ( i sen that in <engine managment advanced tuning >)

have anybody change the throttle body to a much more bigger diameter ?
if any one of you met that question ? also

why they appear this question ? help
and how can solve that ?
if the uprev can solve this question ?

Cos now i have idea to change that to bigger diameter

 

I'm sorry your post is unclear nor is the pic you posted.

 

hello , Sam , I have explain that question with the word in that book . thanks you

 

Enzo,
I think the answer to your question is that you will need uprev. I went from 70mm to 90mm on the VK56 and it was in safe mode until I got an e-tune to eliminate codes and I also had to do an idle reset and throttle relearn. Best bet is to find a good tuner , explain your mods then get some log runs to put you in the ball park. If you need contact info I know two great uprev e-tuners just send me a pm.

 

You're rocking a VK56 and you don't tell us??

Links to build thread please!

 

I wish I could rock it in a G. It was from my Titan . I had JWT S2 cams , headers, 3 in stainless B pipes ( Deleted 2 of the 4 cats) 3 in Y pipe into 3 in remote cutout, 3400 stall , transgo Shift Kit , LS7 90mm throttle body and modified IM. Tuned by RandyB and it would rape my G as it stood. I miss it but not the 12mpg.

 

Hi,S,the car is 11G37S 2DOORS, also met this question after change the throttle body ?
you have met ? thanks share some contact info how to tune , thanks .

 

Sam,
no , not VK56, i have a vq37vhr 11g37s to tune , have you met this problem ?

thanks .

 

Enzo I sent you some contact info and hopefully you get your problem worked out.