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yaris2010RS
01-21-2013, 10:30 AM
Hey all, After working on a friends Neon i cam across an odd discovery and wondered if this would work on the yaris.

We were replacing the cam sensor which on his Neon is what supplies the RPM reading to the dash..... While the sensor was unplugged it appeared to remove the MAX RPM cutoff. Mind you, we were unable to know what the actual car RPM was and my friend made us stop because it sounded very very high and he still had to drive the car home.

So now im wondering, would this work on the Yaris? kinda like how we can remove the speed limiter by unplugging the speed sensor (or dash? cant remember the details)

I do realize on a stock Yarii a higher RPM would most likely be the death of it but on a built engine this could be a great start to test a higher RPM with stock electronics.

CTScott
01-21-2013, 11:04 AM
Hey all, After working on a friends Neon i cam across an odd discovery and wondered if this would work on the yaris.

We were replacing the cam sensor which on his Neon is what supplies the RPM reading to the dash..... While the sensor was unplugged it appeared to remove the MAX RPM cutoff. Mind you, we were unable to know what the actual car RPM was and my friend made us stop because it sounded very very high and he still had to drive the car home.

So now im wondering, would this work on the Yaris? kinda like how we can remove the speed limiter by unplugging the speed sensor (or dash? cant remember the details)

I do realize on a stock Yarii a higher RPM would most likely be the death of it but on a built engine this could be a great start to test a higher RPM with stock electronics.

Theoretically yes that will work. I have done a bit of experimentation on the bench with bypassing the RPM limiter, but never tried it on a live engine for fear of doing damage. The ECM does monitor the CAM signal, so completely eliminating the input will log a DTC and may cause the ECM to go into limp mode.

The method I used is similar to what I do with the speedometer signal for driving metric instrument clusters and having them display and increment the odo in miles. I monitor the stock signal and modify its output. So, in the case of RPM, I simply copy the OEM signal until it approaches the rev limit, and then I output a signal that is less than the rev limit. My fear with doing this is that if things that the ECM does are timed to this signal, very bad things could occur.

cali yaris
01-21-2013, 11:32 AM
A built motor will require more than stock electronics.

Fooling the ECM might work to defeat the rpm limit, but I'm not sure how you'd tune a boosted car like that, aren't fuel maps done by rpm?

AEM EMS + Boomslang is a plug 'n play standalone/piggyback hybrid. If this had been available when I did my car, it's the way I would have done it.

CTScott
01-21-2013, 12:26 PM
A built motor will require more than stock electronics.

Fooling the ECM might work to defeat the rpm limit, but I'm not sure how you'd tune a boosted car like that, aren't fuel maps done by rpm?

AEM EMS + Boomslang is a plug 'n play standalone/piggyback hybrid. If this had been available when I did my car, it's the way I would have done it.

Correct - The fuel maps would likely be an issue, which is part of my fear in testing this on a live engine. With a piggyback you could feed it the real signal and the ECM the fake one, but that still only helps for fuel, not for anything else that might be timed off of the signal.

yaris2010RS
01-21-2013, 01:06 PM
Thats kinda what i was thinking also.

i was thinking "Budget build" on a stock, with the stock ECM, A piggy back, and a built motor that can handle and benefit from a higher RPM.

Im hoping to park my Yarii soon and test from that. Im hoping the signal, like the speed signal goes through the ECM and cluster but takes the feedback from the cluster?

CTScott
01-21-2013, 01:14 PM
Thats kinda what i was thinking also.

i was thinking "Budget build" on a stock, with the stock ECM, A piggy back, and a built motor that can handle and benefit from a higher RPM.

Im hoping to park my Yarii soon and test from that. Im hoping the signal, like the speed signal goes through the ECM and cluster but takes the feedback from the cluster?

Speed goes from the tranny to the cluster and then from the cluster to the ECM for non-ABS cars. And, from the wheel speed sensors to the ABS ECU to the Cluster to the ECM for ABS equipped cars. Either way, you can still have the speedo work while having the ECM not see the speed signal.

yaris0985
01-21-2013, 02:16 PM
i got a dodge neon 2000 (2gn) on the tranny you have a wire (dont remember the color) is the "Speed sensor" you have to make a extension to inside the car and make a switch ON/Off

that gone make when you hit 180km/h you shut down the switch you pcm think you are at 0km/h and continue to push gas (until you reach 6500rpm)

But you need a GPS, because if you want to put back the switch at ON you pcm gone freak...... because you are over 185km/h, but as soon the switch if OFF your mileage is not added...

if you want go on www.clubneonquebec.com and look for "Pat Tuning"