2010 camaro afterburners project, ne

Hey guys Im new here and working on a project that has officially fallen out of my limited electric wiring knowledge. In short, what I am trying to do is make it so when I press the gas pedal on my car, a set of leds mounted next to each exhaust pipe hole on the rear diffuser, will get brighter with more throttle. The car I am working on is a 2010 camaro, it has an electronic throttle control system. From the gas pedal there is a purple wire that sends the throttle input to the cars ECM. How can I tap into this signal and use it to control the amount of voltage being delivered to my leds? The desired effect is this, at idle with no throttle input you can see these orange leds I have already wired up to my license plate lights. When more throttle is applied a second set of orange leds will get brighter depending on the input. This will make the car look like it has afterburners.

I'd suggest adding a resistive TPS and using that to control whatever (maybe a PWM circuit to increase LED brightness). Of course, if you want to intercept the OBD codes....

Car is ETC as you mentioned. Is it a V6 or V8? I can only speak from experience of the V6-3.6l DI engine You have a pedal position sensor you can go by, or you can go by the TPS sensor. Both are redundant, there is two Pedal Position and two TPS sensors. I would suggest going off of the pedal position because TPS isn't always going to go WOT if you have your foot to the floor. You should be able to find a full scale and half scale wire from the pedal assembly. Pedal connector should have 6 wires in total. That will take care of your input signal. Now you need to find a circuit that will give you a variable output based on a variable input. Some sort of amplifier. Are the LEDs wired for +12v already? Something that will scale your 0-5v pedal output to 0-12v is what you would need.

You need to be EXTREMELY careful tapping anything in to your TPS or APP signals. These signals are redundant for a reason - they are constantly being compared to their counterpart for errors. If an error is detected the ECU will go in to limp mode and your afterburners will only look ridiculous as you drive at 20mph at WOT. :) You can obviously go about this many different ways. Your 0-5vdc output may be enough to satisfy you, but you'll need to buffer the APP through a high impedance op amp and then drive a transistor circuit to power the LEDs. I, personally, would use a high impedance analog input circuit going to a microcontroller that is capable of a PWM output. You could directly scale the analog input to the PWM output for linear light throughout the majority of the scale. Sounds like a fun project. How much current do the LEDs require?Kevin Pierson

Thanks KPierson, You filled in the bits I didn't have a chance to comment on. High impedance is a must. There is a correlation check between the two APP signals with a calibrated tolerance/offset. If you drag one signal down by driving your external circuit you do run the risk of setting the MIL and most likely going into limp home mode.

Hence why I suggested a separate TPS. From memory, the common older Jap units usually have a 10k pot, and that could be used as R2 in a circuit like... The cap C1 would have to be resized and maybe R3 (or R1?) increased if the LEDs are not to be off (ie, 0.1% on) with zero load pedal... I can recalc the values and check TPS specs later....

Adding a separate TPS is probably more hassle then it is worth. Maybe you can attach something at the APP side but not at the actual throttle body. Stick with a high-impedance circuit and you should be fine. You could also tap the HFM for a load signal but it is frequency based. (On the V6) Potentially requiring another component to deal with frequency to voltage conversion. So you have two options if you can find an "out of the box" solution. Analog input 0-5v or a frequency input preferably controlling a PWM output. If you want to decouple yourself completely from the vehicle ECU you could always add a MAP sensor for use as a load signal. You should be able to find a 1 BAR sensor relatively cheap either new or used.

Did you do anything with this?Kevin Pierson