[Mk2] [Turbo] ST205 Chargecooler Installation Guide (non 56k friendly)

[Daemonslayer]

hi toxo,
nice thread to follow!
i have a guy buliding my custom heatexchanger for the front.Its without hose pipes.instead its for earls fittings.so i have more space for a bigger rad.
now this thing is large.i asked myself if there will be a problem with the heat of the engine water from the rad behind it?i completly cover the stock rad.
will it be ok or suffer a lot?
bot rads are from alloy.the engine rad has big fans and a shroud on it (misomoto style).

[toxo]

I haven't had any noticeable rise in coolant temps and I have the aircon radiator as well.

[toxo]

interstingly enough, I've also found documentation to state that the Intercooler Fan ECU is also different in the Gen III. Where by one wire goes between that and the cars ECU to override the engine bay temp for switching on the fan.

Gen I/II's don't have any integtration between the cooling fan ecu, and the car ecu.

Tell me more...

[>PETE<]

See here: http://www.mr2oc.com/showthread.php?t=157628

There was another post about it, which I can't seem to find. Bascially the Cooling fan (intercooler fan) on the Gen III is different from the Gen II. It accepts an extra pin from the cars ECU. This allows it to override the normal operation if required to run it longer.

They did mention the different part number on the Gen III Cooling fan ecu as well to help enforce this 'difference'

[>PETE<]

Finally found the other thread on the cooling fan. See here!!


http://www.mr2oc.com/showthread.phpt=37 ... ng+fan+ecu

[>PETE<]

OK, I have new information to update you guys. I've finally solved the ELD (high electrical load) pin from always being 'on'. It turns out this is caused by 2 ECU pin on the Gen III. The ELD pin, which connects to the headlamps and defogger system, but also the ABV pin (look at ST205 ECU diagram as some of the Gen 3 MR2 ones call it a second CF pin)

Unfortunaley I don't know what this normally connects to on the Gen III, but I do know that when the ABV pin is grounded, the ELD system operates normally. I did manage to find out that the pin on the Gen III runs down the body loom to the front of the car, but from there I have no idea.

If anyone has a REAL Gen III wiring diagram I would love to get a copy, as all the copies I have are from the Gen II.

The cooling fan is now working correctly, now I have the later revision Cooling fan ECU too! Power steering ECU, I'm working on.

Toxo, thankyou for all the input, its been of great assistance. Its only taken me 1 year to now sort out this ELD Issue!

[ELS]

Not sure what you mean by ELS?

Moved the pump today as over the year since it's been fitted I've smacked it into a few things. It was a little bit too low in hindsight Nice and simple, rotated the bracket on the gearbox through 180 degrees then split the clamp from the mount and rotated that through 180 degrees as well. Lovely job, all fitted nicely but I had to cut the pipes shorter which meant draining the coolant, refilling, bleeding again etc. Ball ache!

Hey toxo,

You think you could do me a massive favour and take a few pic's of your pumps new location?

I understand the theory of how this all works but just wanted to see how the pipework was run into and upto the pump?

I take it both the pumps inlet and outlet pipes now point up to the chargecooler core, correct?

Did you use any silicon elbows or reducing elbows on the pump aiding its location?

Pics if poss would defo help.......

[toxo]

Short answer is no, because I don't have the car at the moment I will draw you some pictures though!

[ELS]

Thanx bud don't want you to go out your way, when you getting the car back?

If you could just answer a few of the questions i mentioned earlier i'd be well happy!

[toxo]

I was meant to have it back last week... long story.

I knocked up a few terrible diagrams in mspaint...

Diagrams are done as though you're looking at the gearbox this way:


My original pump location on gearbox. Black dot is the filler hole for the transmission oil:


Bracket rotated through 180 degrees, contacts the gbox filler bolt:


Undo the 2 bolts marked in red to seperate the 2 parts of the bracket:


Rotate the top part of the bracket through 180 degrees so that the pump is angled off towards the passenger rear wheel.


You have to do it this way as the 2 bolts that connect the 2 parts of the bracket together are off centre, so if you don't swap it all about not only does it contact the gbox oil filler but it also catches on the gearbox itself.

As for the hoses... with the bracket shuffling I did above, the pump is basically at the same height as the undertrays, so the hose that goes from the pump to the radiator just goes straight forwards:

This is how it looks from the passenger side rear wheel:



The hose that feeds the pump from the chargecooler core has got a 90 degree silicon hose on it, to go straight upwards:



That one is a little bit tight around the clutch hose, but I have recently replaced this with a goodridge braided one, so I'm not too fussed if there is a bit of rubbing.

[ELS]

Excellent work toxo your attention to detail is second to none!

Thanx very much bud, well chuffed!

[toxo]

your attention to detail is second to none!

Except when I'm meant to be sending you money for gearstick surrounds I guess...

[ELS]

.......you said it! Nether the less still a happy bunny, cheers man.

[black gts]

just to add abit , i got the inlet pipe cut off and turned 180 so i could put it in the engine bay just forward of the charcoal canister
inlet temps are good

[toxo]

Converted to the ST205 ECU today. Basically had to remove 2 pins from the MR2 loom.

Referring to this diagram:
http://st165turbo4wd.hp.infoseek.co.jp/ecu_pinouts.html

Stock rev3 turbo ECU is 89661-17460
The GT4 ECU I have is 89661-2B840

Remove the FAN pin from the 26pin plug, which connects to the fan controller. The cooling fan, if you have it connected still, will continue to work. This is just an override to allow the ECU to turn the fan on in an emergency.

Insert new pin in place of FAN. The ECU will ground this pin to turn the chargecooler pump, so this should be connected to one side of the coil in an ignition live relay.

Remove the NEO pin from the 26pin plug, which connects to the optional TRC controller (you CANNOT run the GT4 chargecooler and TRC at the same time anyway so this is no loss).

Insert new pin in place of NEO. This should be wired through to the MTT pin on the pump.

If you have TRC you may have to remove the IDL2 and TR2 pins - my loom didn't have these pins so I just inserted new ones and wired them through to M+ and M-.

Likewise for the LEV circuit - this goes through the level sensor in the chargecooler core. The float completes a circuit when there is enough coolant and breaks the circuit when there is insufficient coolant. It should have 1 wire connected to ground and the other connected to the LEV pin. In the diagram this replaces VTO2 which I again didn't have a pin for but I believe it's TRC related.

I pulled PSCT out. I originally pulled the PS pin and my power steering didn't work. Put PS back, pulled PSCT, power steering works as it should. Job done.

Edit: Added a bit more info above on ECU pins

[toxo]

BTW, if anyone's interested this is the exact same ECU as the one I used, JDM ST205 (but the sale is nothing to do with me).

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0575334387

[zappa fan]

Hi Toxo, >Pete< and all the guys on this thread.

I am just about to fit a ST2O5 charge cooler to my MR2 REV2. Do you think I can switch the pump on and off using a water temperature thermostat switch, located in the water hose pipe, (inlet or outlet side?)
next to the core body. Or, is it better to pick up on the air temperature in the core body ,in order to switch the pump on and off? Is that what the wires coming out of the core with the plug on the end was for?

If any of you are still out there watching this thread, I would appreciate your advice. Thanks Toxo for starting this thread and putting in so much effort, it's been really helpful .

[toxo]

Do you think I can switch the pump on and off using a water temperature thermostat switch, located in the water hose pipe, (inlet or outlet side?)

That would work, yes.

Or, is it better to pick up on the air temperature in the core body ,in order to switch the pump on and off?

I would imagine both solutions would have the same end result. I think monitoring the water temp would be a bit more delayed than monitoring air temp.

Is that what the wires coming out of the core with the plug on the end was for?

No, that's a level sensor. It is a short if there is enough coolant, and breaks the connection if the coolant level runs low.

[zappa fan]

I think your right,about the water being slow in picking up the fact that the air is geting to hot.I was thinking if i set the water temp sensor to kick in the pump at a very low water temp i would have a constant and steady water temp that with trial and error(or some one from toyota telling me the water temp should be a constant ?)would give me the nessasary cool charge and not have the pump running all the time. Thanks again toxo.

[Drifter]

Been a while since i posted, but was looking into siwrl pots, and came onto this thread, best to just run the pup constanly, i use a bosch pump though.

Also question, anyway to check if my fans are working? As they never seem to come on, would just have them on cosntant if i knew how.