Any vendors selling revised throttle sensors?
#22
SUPERCHARGED RED ROCKET ------------------Master-Moderator
My main concern, is won't the brushes end up wearing out faster, due to the additional pressure being applied by moving the cover forward
#23
Legacy TMS Member
Thread Starter
That's a good question. I'm sure Ford designed the carbon traces to withstand years of use/wear but I am not sure that it will self-calibrate for the WOT position. There were some S197 GT owners that datalogged TPS and found they couldn't get more than 85% throttle. The PCM can self-calibrate for closed throttle/idle because that is the zero position. However, a potentiometer would essentially have to sweep to a certain position on the carbon trace to send out the "WOT" signal due to the change in resistance on that trace.
#24
That's a good question. I'm sure Ford designed the carbon traces to withstand years of use/wear but I am not sure that it will self-calibrate for the WOT position. There were some S197 GT owners that datalogged TPS and found they couldn't get more than 85% throttle. The PCM can self-calibrate for closed throttle/idle because that is the zero position. However, a potentiometer would essentially have to sweep to a certain position on the carbon trace to send out the "WOT" signal due to the change in resistance on that trace.
I think the data logging you're referring to wasn't exactly relevant to this. In the past, people have found a mismatch between pedal position and throttle position. If the computer is reading pedal position correctly at 100% but not opening the throttle all the way, then there is probably engine management stuff going on that you have no control over by messing with your throttle assembly. The best you can do is give the computer 100% pedal position; it might still decide that you really don't want your neck snapped back by a hard shift and only open the throttle 85%. A tune will do something about that.
#25
SUPERCHARGED RED ROCKET ------------------Master-Moderator
I have one other concern: what is the risk factor of the brushes breaking, once the cover is pushed forward. In other words, will the additional pressure cause damage to the brushes, from the cover bending them further onto the carbon trace.
Last edited by m05fastbackGT; 8/6/08 at 11:27 PM.
#27
SUPERCHARGED RED ROCKET ------------------Master-Moderator
#28
Cobra Member
Join Date: November 27, 2004
Location: Albuquerque, New Mexico
Posts: 1,303
Likes: 0
Received 2 Likes
on
2 Posts
but I am not sure that it will self-calibrate for the WOT position. There were some S197 GT owners that datalogged TPS and found they couldn't get more than 85% throttle. The PCM can self-calibrate for closed throttle/idle because that is the zero position. However, a potentiometer would essentially have to sweep to a certain position on the carbon trace to send out the "WOT" signal due to the change in resistance on that trace.
If a $300 joystick can properly implement a functioning self calibration routine, don't tell me a $30,000 car CAN'T do it.
Any time you use a pot in critical applications, you have to spend a bit or resources to make SURE the signal you are getting back is the correct signal. That means calibration. That means having multiple traces so you can compare the results. That means having VERY effective routines to identify any kind of fault and fail safe.
As for those with 85% throttle, are you sure that is calibrated in throttle OPENING (aka: 0% is fully closed an 100% is throttle plate at 90 degrees), or is it simply calibrated in percent of full scale voltage (VERY common in electronics)?? I don't know how it is calibrated, but I wouldn't get too worried about 85% until I KNEW how it was.
#29
Legacy TMS Member
Thread Starter
If a $300 joystick can properly implement a functioning self calibration routine, don't tell me a $30,000 car CAN'T do it.
#30
Bullitt Member
Join Date: June 15, 2008
Location: NY
Posts: 448
Likes: 0
Received 0 Likes
on
0 Posts
As for the pot being at fault. It does recalibrate. There is a routine to recalibrate throttle position. It looks like it needs some tweaking in some cars. Not so much in others.
#31
Cobra Member
Join Date: November 27, 2004
Location: Albuquerque, New Mexico
Posts: 1,303
Likes: 0
Received 2 Likes
on
2 Posts
Ok. So you think the pots (multiple, five actually) in the $300 joystick are better than the the pot that is used in the drive by wire pedal assembly??? Considering I can buy replacement pots for less than $6 from the joystick manufacturer or less than $2 from Digikey, I REALLY don't think the joystick is using better hardware!
Actually, I KNOW they aren't. I've taken the joystick pots apart before and comparing the guts of these pots to the pictures posted above of the insides of the TPS, well, there IS no comparison! The TPS is built WAY better and WAY more reliable.
Actually, I KNOW they aren't. I've taken the joystick pots apart before and comparing the guts of these pots to the pictures posted above of the insides of the TPS, well, there IS no comparison! The TPS is built WAY better and WAY more reliable.
#32
Legacy TMS Member
Thread Starter
http://www.crownvic.net/ubbthreads/u...gonew=1#UNREAD
There are also other cases of DBW systems exhibiting unusual behavior and not just in Fords. I wish they had stuck with the cable throttle.
There are also other cases of DBW systems exhibiting unusual behavior and not just in Fords. I wish they had stuck with the cable throttle.
#34
Legacy TMS Member
Thread Starter
I can appreciate the simplicity of DBW and the reduction in NVH from not having a cable. However, the GM rental cars I drove (G6 GT and Impala) had severe throttle lag. I'm grateful that my Mustang does not have throttle lag because the lag is a much bigger problem than dead-play.
Thread
Thread Starter
Forum
Replies
Last Post