hi all!! so, the guy in the dealership told me that the tC does not use a timing belt. the, he also told me that the tC uses some kind of technology that regulates the power and gas consumption of the car saving energy. is that true?? it didnt make much sense to me, i didnt even know that existed.

thanks guys!!

 

Well, technically he's right about it not using a timing belt. It uses a timing chain! ba-dumm PSSSHH!!!

IMO I wouldn't put too much stock in what the guy in the dealership is telling you about the car. He's trying to sell things.

 

that 'regulate power and gas consumption' sounds more like drive-by-wire.

 

ohhhh, ok. anyways, i still love the scion tC!! its just that if those things were "true", i would love the tC even more!!

thanks for the replies!!!

 

i'm also assuming it refers to vvt-i

 

whatever the case, Toyota should really get some type of reflash available for us to reduce/eliminate the gas pedal lag.

 

Its a mechanical thing not related to throttle by wire at all.

And yeah...timing belts are so over-rated! I took mine off my tC and gained 600hp!

 

VVT-i

 

^werd

 

neah... it's because of the drive-by-wire.

 

https://www.scionlife.com/forums/vie...t=throttle+fix

 

Well I'm pretty sure that works because it already engages the accelerator... so techincally speaking the gas is always "engaged" a little bit, which is why it "eliminates" the lag

Also, apparently several cars can be "retuned" to give a smoother, faster response... a few examples are the Civic Hybrid, the STi, and apparently the LS2 GTO already has an "excellent response," according to this thread over at SS...

http://www.standardshift.com/forum/v...r=asc&start=15

I don't see why Toyota couldn't possibly redo our DBW systems a little better to reduce the lag

 

^^ yeah.. that's what people are really just doing...

and i dunno why either... i'm fine with the lag now... you just get used to it.

 

Alright, hear me out. I work in automotive software so I doubt the DBW takes more then say 5ms to engage.

Here is my proposal, please read it all before calling out problems and lets leave this as sciontific as we can.
My thesis is that the delay is caused by the intake or bad programming instead of the DBW and here is why. The delay is only known in the very first part of the pedal. Proof of this is such, you can do the 'fix' and not change the RPM's (Its possible althought not 100% of the time). This means the pedal has moved, but no more air is getting through. There are 2 possible causes, mechanical or software. If it was software then the code would have to still say no pedal pressed. If it was Mechanical the intake moved, but not enough to let more air in. The DBW Stinks theory is proven wrong becaus the RPMs will continue to be normal and not jump after pressed that tiny amount.

When this fix is applied, if the DBW was causing a delay...there would still be a timing delay. Just because its starts in an advanced position doesnt mean that a software lag goes away. This refines the two possible conclusion, 1. the intake as mentioned above. 2. The DBW is programed wrong such that the first couple of positions are programed to zero instead of 'pressed'.

Both 1 and 2 are logical solutions that work with the 'fix' because the fix would eliminate either the intake problem or puts the pedal to the point right before it actually gets out of a 'non pressed' state.

Now, what originally caused this problem? Who knows, it could have been bad software (reason for a reflash of DBW) or it could be that the pedal was made out of spec to what DBW was made (still a reason for a reflash of DBW).

So it could possible be the DBW system, or it could be the mechanical solution.

I work in software so I must abide by the code and say its a mechanical fault!

 

I would lean toward a mechanical fault, but with the DBW.

I don't know EVERY working of the DBW system, but somewhere the mechanical action of your foot on the pedal has to be transformed to electrical. Maybe with a potentiameter. There could quite possibly be a slight physical gap between the lever and the potentiameter. To prevent it from resting on the potentiameter causing a high idle. IF THIS IS HOW IT WORKS!
I work with variable frequency drives and stuff at work, and they use Potentiameters all the time to control speed because of the variable voltage drop.

I just took a stab at it.
I do know that I've heard other very very similar complaints with lots of DBW systems. I.E. - BMW's.

Z

EDIT - Also if it's a POT if you're familiar. It's just a variable resistor. So if this is the coil windings ////////////////////// one end would be 0 V drop, and the other whatever the voltage is. Like say... 5V.
It could be that the first two or three windings are still full voltage drop (idle) and therefore requires more movement farther down the POT before it senses a change.


Anyway, that's just some of my guesswork. I wouldn't think a TB or Intake. Manufactureres have been building those for several decades. They should have that down. I think it's in the transfer of mechanical to electrical (DBW) which is relativley new.

 

Yeah, that could be the culprit.