# OBDII Megasquirt TPS issue...



## ac_morris (Sep 6, 2006)

Hi guys, 
Im doing a bit of research regarding some management i have bought ... looking at the wiring diagram below...
http://vwtech.no-ip.info/downloads/g3aggecu.pdf
I have worked out that theres the following wires for the throttle module..
T28a/25 white J338(2/-) Throttle Valve Module
T28a/26 red/grey J338(8) Throttle Valve Module
T28a/27 grey/yellow J338(3) Throttle Valve Module
T28a/28 black J338(1/+) Throttle Valve Module
T28a/19 red/blue J338(5) Throttle Valve Module
T28a/20 red/white J338(4) Throttle Valve Module
obviously i have the positive and the negative value but i need the signal reference for my management..
Can anyone point me in the right direction of which wire is the signal wire, i have read a lot of people are running a passat throttle body, and an obdi throttle body, but i see no point in buying new parts if i can get them to work off this..
Also i have read that the throttle body provides 11V at WOT as standard, im assuming people address this by running a 5v feed to the throttle body instead??
Cheers in advance
Dicky


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## need_a_VR6 (May 19, 1999)

*Re: OBDII Megasquirt TPS issue... (ac_morris)*

You trying to share it with a stock ecu?
The OBD2 tb is 5-0v, which is backward for most standalones. 
On the TB Pin 4 and Pin 7 are either 5v or ground, and 5 should be the full range signal. If you hook it up and it's 'backwards' swap 4/7.


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## ac_morris (Sep 6, 2006)

hey mate,
nah i am trying to wire in some management i have.. 

looking at the wiring diagram i have posted above i have pins 1 and 2 as the positive and negative..
which is why i am struggling to work it out.. i think i will have to go with what you said though..
so i should work of pins 4 and 7 as the pos and neg and then 5 as the signal...


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## need_a_VR6 (May 19, 1999)

*Re: (ac_morris)*

The download won't work for me right now but I think 1/2 are for the idle motor.


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## ac_morris (Sep 6, 2006)

awesome mate, i shall check that the voltage is ok at 5v.. if not i shall have to work something out.. cheers for your help man..


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## need_a_VR6 (May 19, 1999)

*Re: (ac_morris)*

The voltage will be whatever you feed it with http://****************.com/smile/emthup.gif


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## ac_morris (Sep 6, 2006)

*Re: (need_a_VR6)*

you my friend are a very helpful man...
All i need now is a 2E window dizzy because the AGG is a 1 window hall dizzy and i think i have all the angles covered...


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## need_a_VR6 (May 19, 1999)

*Re: (ac_morris)*

Does that motor have a 60-2 VR crank sensor? If you're using a V3 board it's very easy to run the VR sensor.


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## ac_morris (Sep 6, 2006)

*Re: (need_a_VR6)*

i dont actually have megasquirt, i have something called mr.turbo, its a south african software... i gave it the title megasquirt because i knew more people would look at it haha
I cant run a crank sensor with this software, it works purely off the distributor, which is why i have to run the earlier 2E distributor


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## need_a_VR6 (May 19, 1999)

*Re: (ac_morris)*

Good call, it got my interest







Much luck!


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## ac_morris (Sep 6, 2006)

*Re: (need_a_VR6)*

cheers for the shout...
Basically i am in afghanistan and have got limited internet access, 60odd of us all sharing a 1meg connection through wireless routers, so hunting around for information online is a bit of a nightmare and looking at photos is impossible..
But while i was out here (and while my chargers away having brackets fabbed up) i thought i would look at the wiring diagram that mr.turbo provide and see if i could sort out all the wiring..
My first port of call was the 28pin connector at the front of the engine bay that allows the engine to be removed with all the sensors in place.. I managed to find the diagrams online in pdf format so sat down and worked out each wire.. so now when i get home i can go to a scrappies and pick up one of the connectors and have a "plug and play" style system..the only issue i saw was that of the air temp sensor and the throttle body as the air temp doesnt run through this connector and throttle body has about 7 wires showing.. which is where you came in...
The biggest problem i have is with the software itself, it seems like all the people who run this software in South Africa throw it on and then take it to a dyno to have it mapped, so trying to find out the best settings is a nightmare also.. I have managed to source bits of information but i think it might come more to light when the system is live on the car and i have downloaded the base map for the car, although the ignition curve will be all to pot as the map is for the NA 2L lump and ill be running a charger so will need to ignition map to retard with boost not advance as it would NA but that seems an easy fix
I asked around to see if i could run the AGG distributor with some kinda software change but apparantly not, so i need to change it to the earlier 2E but thats a piece of piss, one bolt jobbie..
When it came to the fuel pump, the wiring diagram they have shown is a bit misleading as it has the fuel pump live on the injector live wiring.. because of the whole "if you have a crash the pump must switch off" thing i have checked out the wiring diagrams for the vw and am working off the old KJET idea, so i will run a kjet relay in place of the mk3 fuel pump and then the wiring will be.. 
clocks to pin 7 of TP100 (for rev counter), pin 1 of TP100 to coil -ve, coil -ve to the fusebox..
I have now moved on to the pipework for the charger and have come across another problem i am trying to address.. I picked up a chargecooler with the pre-rad, pump and reservoir quite cheap but didnt realise it only had a 2' outlet on it.. so i have just started asking the questions online to see whether this will be suitable to handle 5psi on the standard pulley at around 180bhp.. some people seem to think it will choke and i will need to run bigger pipework some people are saying it will be fine..
After reading about air speeds increasing with smaller diameters i am tempted to run 2.5' pipework so that i dont pick up too much heat with the air flow as the eaton can run quite hot has standard.. but then my next port of call was whether to just run 2' reducer samco's to fit the chargecooler or to look at having the outlets cut off and have 2.5's welded on.. 
I wait and see..
ohh just because you have spent the time reading this.. 








cheers again
Dicky


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