# tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0



## AutoCrosser11 (Jun 23, 2004)

I was wondering if I could get some help connecting my TPS and IAC to my MKIV AEG 2.0. for the time being I am only planning to run fuel and control spark later on. I also have all my other sensors and rpm working, and got switched power to the MS. So the only thing left is the TPS and IAC.
I built the board for the PWM idle valve with the tip120 and followed all the instructions in the megamanual. but I am just no good reading the wiring diagrams. so maybe some one can help me out please!
here is my wiring diagram for the connector on the TB: 








I know my tps is reversed and the idle valve is also reversed. I also been told that the voltage is wrong coming from the stock ECU to the tps. I have also read that I can swap the ground wire and the 12V wire to switch it back to 0-5V. how do I exactly go about doing this? it would be really handy if some one could just fill in the blanks for me.
db 37 pin 22 -> what do I connect this to?
db 37 pin 26 -> what do I connect this to?
db 37 pin 30 -> what do I connect this to?
which wire becomes the new ground on the stock connector?
thanks for any help.


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## need_a_VR6 (May 19, 1999)

*Re: tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0 (AutoCrosser11)*

If you're still using the stock ecu for some control, I'd leave it all alone. You can just ground the MS tps wire to keep it from doing anything stupid, and tune your enrichments via MAP. Once you're on MS full time, you just need to swap the 5v/ground (looks like T8/2 and T8/5) to get the tps to read right. The idle motor is T8/7 and T8/8 you will most likely have to play around with settings though to get it to work right.


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## AutoCrosser11 (Jun 23, 2004)

*Re: tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0 (need_a_VR6)*

Great, sounds easy enough! Which tps pin on ms do I need to ground? Also will the engine idle fine when it's cold or will I need to modify the tb cable so that it is open a little for cold starts?


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## need_a_VR6 (May 19, 1999)

*Re: tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0 (AutoCrosser11)*

TPS signal, DB37 pin 22. After you ditch the stock ecu, the built in idle motor should be able to open enough to give you a decent cold idle. You will have to fiddle with it get it working right. I know that the OBD2 VR6 tb works similar and I got it to work.


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## AutoCrosser11 (Jun 23, 2004)

*Re: tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0 (need_a_VR6)*

thanks for the help. I will be sure to ground pin 22.
I guess maybe I should have been a little more specific though with my question. will I have any cold idle problems while pwm motor is still connected to the stock ecu? basically with the stock ecu not controlling the injectors will it still be able to control the PWM motor correctly?


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## need_a_VR6 (May 19, 1999)

*Re: tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0 (AutoCrosser11)*

If you only unplug the injectors I think the idle motor will still function normally.


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## AutoCrosser11 (Jun 23, 2004)

*Re: tps and iac help on MKIV 2.0 megasquirt 1 PCB 3.0 (need_a_VR6)*

cool, thanks for your help http://****************.com/smile/emthup.gif


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