Nick Winsor

Digging up an old thread here, sorry! OK so I'm still setting things up for the installation of the ECU, I have spoken to my tuner, and he has suggested to me that the factory triggering on the 3SGTE is not really ideal for doing ignition tuning. He has suggested that I install a crank angle position sensor, and retain the factory cam position sensor as well. Does this sound right? I have found an off the shelf option for a crank trigger set up for my engine, in the form of an Electromotive trigger wheel and bracket. I believe the wheel is a 60 tooth, with a flat section on the wheel that I presume is a home position. Will this trigger wheel work with this ECU? Thanks again, Nick

Ah, ok that makes sence. So I've finished cross referencing and have made an I/O list and connection diagram. I just want to confirm that I won't be connecting a solid unswitched 12V? The only ECU had one, is all. There are four grounds in total on the Xtreme. Pin 25 and 34 on each plug, I think. Anyway, there are 2 grounds from my factory loom. I was going to connect one of them to the two 25s from each plug and the other to the two 34s. Â I have another ground that went to the factory ECU labelled E1 engine ground, that was used to connect the shields from the Knock Sensor and the oxygen sensor, and also went to the ECU. Should I join that up to the other Grounds? When I connect my knock sensor and oxygen sensor earths to the new ECU I should connect them to Sensor ground, is that right? There is another ground point on the Xtreme called Sheild ground, but in the diagrams it says to use sensor ground? In the case of a digital input, if I drive low, can I just take the other side of the switch to the chassis? Thanks again!

Sorry to post so many multple messages, I have been doing some more research and have found my ISC is merely a 2 coil valve, not a stepper motor, so its all good in that regard - the power supply wiring I'm happy with. Also, the lamp, defogger and stop wiring, all just feedback to increase revs for the load. So I'm happy with that too (Will not be used) I'm happy with the wiring for the injectors, the ignitor (would still like confirmation the standard injector resistors and ignitor are ok to use). Have also done research on the Circuit Opening Relay, and now I'm happy with that too (Google rules). As for the fuel pump control relay I'm happy with that too as I'll just assign an output to it, so the G4 can control high / low fuel flow. EGR VSV is being relegated to the garage floor, so thats cool too. Really the only thing I'm not sure about is the BATT connection and the Check Connector connections. Namely the VF, T, OX2 and OX1 connections. The OX1 connection was labelled in the ST185 pinout diagram as going to the Check Connector but my diagram shows it going to the Oxygen sensor, so thats ok with me. That leaves the VF, T and OX2 connections. Seen as the Check Connector also provides the ground point for the Ingition Coil, do I need to wire these connections? What do they do? I suspect they are redundant but just want to make sure. Do I need to provide the G4 a contant 12V BATT connection? (Fed from EFI fuse as is factory) Not so many questions this time, thanks

One more thing, I have just noticed the negative from the ignition coil actually goes to that Check Connector too, so getting that to interface with the G4 seems to be pretty important. Thanks again

Hi again, Happy Holidays! If anyone has a chance to help me with these wiring connections I'd be really grateful. As I have said, I'm a complete newbie to this but I am an industrial electrician so I like to learn and give things like this a good go myself. Ok so I'm currently working on a speadsheet where I work out which existing wires on my harness get connected to which wires on the loom for the G4. I should be able to work out the majority of it - I have a few issues though. The first is power supply. I have an ISC but I can not see an existing ECU Hold relay - is this something I will have to add? There is currently a solid supply from the EFI fuse (fed from before the EFI relay) which goes to a terminal labelled BATT. There is also a wire from the Starter relay which goes to a terminal named STA (Starter Switch) as well as the Circuit Opening Relay. What do I do with this? Finally there is a feed from the EFI main relay, looped in to two terminals labelled +B and +B1, so there's my power supply. I can't see an ignition relay to connect, and jut need details of if I need to add a hold relay..  I also have both a Circuit Opening relay and a Fuel Pump Control relay - from what I can tell the circuit disconnecting relay is used to completly remove power to the fuel pump, and the fuel pump control relay is to bypass the fuel pump resistor - Do I need to connect these both up to different outputs? What is the fuel pump resistor used for? As mentioned earlier the Circuit Opening relay has a seperate coil fed by the start switch, what is that for? I was planning on driving each injector from it's corresponding Injector output on the G4 - somewhere on these forums I saw a diagram where the injectors were paired on an output - I assume this is in case you run out of outputs and I won't need to do this? I presume the factory injectors and resistors are fine to use? For the Igntion system, In the distributor, the triggers are Falling Edge type, is this suitable for the G4? They also share a common sheild - judging by the wiring diagram on the G4 manual this is not a problem. Is this the case? Is there any issue with using the factory ignitor and just using IGN1? I have removed my A/C system I will not be connecting anything to do with the A/C. T-VSV will no be being used anymore obviously as I will be having electronic boost control. (T-VSV lines have already been disconnected and capped when I installed the now redundant manual boost controller). However, I have a TVIS output, do I just connect this to an auxillery output for my tuner to configure, as is the case for the other inputs / outputs? What do I do with the Check Connector connections? Also, there are connections coming from the Stop Lamp and Tail Light and Defogger. What are these used for, do I need to connect them? Do I need to bother connecting the Exhaust Gas Recirclation VSV? I should be ok with the likes of the ISC, sensors, switches, speed sensor and boost solenoid as I will follow the manual and tell my tuner what I/O I have used. Thanks so much in advance if anyone can help me with these questions, I know there are a lot of them! Regards, Nick P.S I can scan in some diagrams for the ST185 if it helps, let me know.

Oh cool, that's great, thanks! I managed to track down a MAP sensor from an ST215 Caldina, according the all of the forums I have found while google searching, the actual sensor is calibrated the same as the ones from the Gen 3 3SGTEs. Thanks again for your help.

As mentioned above, is there a link anywhere to download the ST205 base map, or if I give you my email would it be possible to have it sent to me? Thanks

Ok thanks for your help! I am currently trying to figure out a way I can mount the sensor up near the throttle body (top mount intercooler feeds straight in to a rubber fitting attached to the throttle body). We have played with the idea of making a new flange on the throttle body with a section of pipe long enough to house the sensor with enough length to attach some hose, but that means we will have to shorten the outlet of the intercooler. We'll find a way I'm sure (I'll be sure to make some sort of heat sheild for the sensor from the rising heat of the engine too). You'd think Toyota would have mounted the factory temp sensor after the intercooler, but oh well such is life! Regarding the Link / Bosch sensor, before I read that I jumped the gun and ordered a Haltech one as the open ended ones on the bosch site seems to be push in types. Anyway, the Haltech one has a 14mm thread, open element. Does the PCLink software have preset calibration for these sensors or am I best to contact he manufacturer and get a chart? And thanks to Felix's comments I am currently chasing down an ST205 MAP sensor. Thanks, Nick.

Hi, thanks for your prompt response! I do not have a wideband presently, I just wasn't sure if the engine would benefit from being set up using Closed Loop Lambda control, bearing in mind this is primarily a street car occasional track day use. What do you think? Regarding the IAT sensor, thank you! I didn't click that the factory one would be being removed with the AFM. So the best location for this is after the intercooler, right before the throttle body (as opposed to before the intercooler like the factory one)? Is there any specific details I need when choosing the right sensor, as in resistance range etc? Thanks again, Nick

Sorry I don't know how to edit posts - I also was wondering if there is anything I haven't considered that I should be organising? Thanks again. I'm trying to do a lot of the researching etc myself and the work as I like to learn as I go and want unbiased opinions.

Hi, I'm not a tuner at all, but I have a basic understanding about what I want to achieve with my car (ST185 Celica). I will be purchasing a G4 Xtreme for it (as I want the on board Knock control) and installing it with my friend (He's an auto sparkie, I'm an industrial sparkie). I am currently trying to get everything purchased / manufactured that I will need once setting this up ready to deliver the car to my tuner so they can tune it. Currently I've purchaced a 3 port solenoid for boost control and am getting a new intake pipe made without an AFM ready to slot in once the AFM is no longer needed. Do you think I should buy a new MAP sensor or should the factory one work fine (I will not be raising boost levels above around 15 psi) Also, should I purchase a new wideband O2 sensor for the installation? My other question is regarding a base map, my tuner told me it would save considerable time on setup and on the dyno, do you know where I would be able to obtain one? Thanks in advance, Nick