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I would recommend ordering the steering shaft pinch bolts and low pressure side crush gaskets (M17). They're both unique parts and incredibly hard to find locally. The high pressure side you could order oem or use any generic M16 washer since it's easy to find.
- High pressure M16 PS gasket: Toyota 44327-30040 (qty:2)
- Low pressure M17 PS gasket: Toyota 90430-17007 (qty: 2)
- Pinch bolt on the steering shaft: Toyota 90080-11555 (qty: 2 in engine bay)
Thank you for this! I was able to cancel my A-1 Cardone re-manufactured PS rack order and I bought a reman assembly from a Lexus dealer. I had previously thought Lexus *only* sold new ones! Along with it I also ordered the three parts in the quantities you detailed.
After seeing a reman PS rack last a mere three months in my mother's LS before it blew out two days ago I will only go with a rack from Toyota/Lexus or with a personally performed or comissioned rebuild such that you did with your SC.
First thing I'll say that NOW the car has been running very well since getting that #5 injector connector replaced again It's up to 85 miles on the break in. Only 415 to go! SouthBend says they want 750 miles to break in their clutch but I don't plan to do anything silly with the car before 1200 miles anyway.
Only little issues exist right now:
--The tach signal doesn't always come on immediately when I start up but then it stays consistent. Most of the time it's fine at startup. Sometimes it takes 10-30 seconds before it comes on. Varies. (I'll get those wires shortened and covered permanently into the harness soon). Maybe I should de-solder and remove the cluster R109 resistor and just leave a jumper in its place?
--I need to repair some of the YellowBox VSS harness wires since my speedo doesn't always get a signal. Or I may just replace the whole harness with a new one. They're only $20 plus shipping from Yellr. OR... perhaps I need to be sure that the screw-on Marlin Crawler mechanical-to-VSS unit on my MKIII R154 is working perfectly. My bet is on the little Yellowbox PnP harness wires since there was some rubbed off insulation that I had to cover in electrical tape the last time I was under the car.
-- A/C function (details below in next post)
-- Power steering rack replacement
-- And of course the rear diff really needs to be rebuilt with the 3.76 TT Auto gears. I knew this would be the case years ago if I ever got this far with my SC but boy, is it ever apparent to me now Zero regrets having a 4.27 Torsen LSD rear while I was NA for many years though. Perfect for the NA 2JZ-GE's powerband, just not good for a GTE's powerband. 1st and 2nd are gone though MUCH more quickly than ever before and are now just too short of course since the engine makes so much more power and torque much lower in the rev range.
Okay... Gerry after your last post I realized I had to review what every one of those A/C related wires on the SC actually does before going further so it was back to the SC300/400 wiring schematics for me and back to reviewing pages 5-7 of your harness thread and then seeing if what I found lines up with my own wiring notes for the A/C.
I looked over this A/C operation description from the SC300/400 wiring TSRM for a while:
Then I did an A/C controller function test (hold down the A/C "Auto" round dial and one of the sides of the toggle switch for "Recirculate"/"Outside Air" and then turn the ignition to ON... and then wait to see if codes are shown and beeped).
From that test I got two A/C fault codes: 12, and 21.
A/C Trouble Code 12 -- Ambient Temperature Sensor Circuit (which is EB1-7 and SC II1-1)
A/C Trouble Code 21 -- Solar Sensor Circuit
Now I know I didn't change any wiring for the solar sensor located on the far end of the driver's side of the dashboard and I did this test during the daytime (though it was cloudy outside) but still I wanted to check it. I had someone hold a flashlight inches above that solar sensor and then ran the A/C diagnostic test again. Still I got a Code 21 error. So maybe I will need to replace the solar sensor... but I will pursue that later. I don't think that is the main issue.
Next I disconnected and removed my Ambient Temp sensor from the bumper and tested it's continuity in accordance with the TSRM:
The Ambient Temp Sensor tested within the specified range so I now know that was good.
I put it back into the car, however I only later realized that the battery was still connected when I plugged it back in. I hope I didn't damage it by doing that since the TSRM seems to suggest that the battery has to be disconnected before you plug it back in :/
...
Anyway, it's clearer now that the A/C system doesn't like some way in which my Ambient Temp Sensor or its shared connection with something else is wired.
So, then... back to my notes to figure out what I did incorrectly:
Gerry, thank you for those pinouts for the A/C connector! I've gone through the SC300 A/C wiring diagrams and updated them with what labels for function that I found:
A/C Connector A2:
Pin 1 -- "A/C Ambient Temp Sensor" -- to EB1-7 and then to SC body plug II1-1
Pin 2 -- "A/C Lock Sensor" -- to intake manifold ground and SC body plug II1-4
Pin 3 -- UNUSED
Pin 4 -- "A/C Magnetic Clutch" -- to SC300 EB1-1 (which feeds into the magnetic clutch relay, Pin 3?)
From your Page 7, Post #98 on your harness thread I know that the MKIV GTE ECU 40-Pin "A" Connector Pin 34 (A/C request signal) and Pin 23 (A/C Mag Clutch Relay Signal) are crucial: https://www.clublexus.com/forums/per...ml#post8364665
So... a little out of order here but...
In the Supra MKIV wiring diagram for the A/C I find that:
Supra II1-31 is from the 40-Pin main ECU connector Pin 34 (which is the request signal). So then that goes into Lexus II1-5 which leads into the SC300/400 A/C controller which will process that A/C signal request! In the SC300 wiring diagram it is the same ECU connector pin that sends the same request signal to the A/C controller. So that one I know I got right.
From the simplified SC wiring diagram on this circuit:
Next...
In the SC300/400 wiring diagrams I see that SC II1-1 and SC II1-4 have a kind of relationship with one another:
SC II1-1 goes to the "A/C lock sensor" (Pin 1 on the A/C compressor connector) and then from the lock sensor a wire runs to SC II1-4 (Pin 2 on the A/C compressor connector) which is the "A/C lock Mag Clutch"
From the Supra harness wiring TSRM I find that:
The MKIV's A/C connector Pin 1 is also for the "A/C lock sensor" and on that harness it goes to MKIV II1-20. So... the SC's II1-1 must be merged with MKIV II1-20 since this refers to the A/C lock sensor on both cars.
Next... the MKIV's II1-26 goes to the other side of the "A/C lock sensor" on the magnetic clutch and feeds back into the MKIV's unique A/C control system. On the SC, this same other side of the "A/C Lock Sensor" is II1-4... which is also SC A/C connector Pin 4 (and a ground). So I should be connecting MKIV II1-26 into the SC II1-4 to make the same circuit operation work.
This, to me, also supports why the MKIV's II1-10 which is another "A/C Mag Clutch" wire just doesn't have a place in the SC's A/C control system. Edit: It can though if a +12V trigger for a fan relay override that is tied to the on/off operation of the A/C compressor is desired for added cooling if your GTE swapped SC lives in a very hot climate or for whatever reason needs an added electric fan to kick on with the A/C. See the link below:
All of those wirings that I just went through above seem be okay for me.
So far so good.
The one that I can't figure out much info on but which I did was to connect Lexus IJ1-2 (which is the SC's normal fuel pump ECU power to Lexus II1-2 for "gnition power to the A/C ECU. I think this is working fine but I thought I'd mention it.
...
Okay, now it comes to my chief suspicion in all of this:
The A/C Connector Pin 1 to EB1-7 to SC II1-1 (which, due to the way I did my harness, got the MKIV II1-20 wire which does the same function as on the SC).
Now during my previous harness work before the engine went in I did route a new (well, used from my spare SC harness) brown 14ga ground wire through my harness from the EB1-7 to SC II1-1.
Two things occur to me to look into from here since I seem to have an A/C Code Fault Code 12 ("Ambient Temp Sensor Circuit") but my sensor tested in good condition:
1) Test the A/C connector Pin 1 to EB1-7 and to II1-1 to make sure those points all have good continuity.
2) Test my stock SC wires that go TO the Ambient temp sensor and EB1-7 and also the other side of the ambient temp sensor connector that connects to SC IN1-4
Maybe I still did something wrong wiring the system (most likely reason for the fault codes and non-operation with the flashing light) but maybe one of the wires going to the ambient temp sensor itself has been damaged in some way that is hindering a clean signal to the A/C controller.
Edit: I think I was so overloaded verifying these circuit paths for both the SC and MKIV that the answer was right under my nose.
I might be wrong but I don’t think so.
If the MKIV’s II1-20 “A/C Lock Sensor” wire is *supposed* to be merged with SC II1-1 which also has the EB1-7 wire that goes to the SC Ambient Temp Sensor... then I think this is what I forgot to do.
I will have to check more but... this may be my mistake preventing normal A/C function.
I just checked continuity between the SC Ambient Temp Sensor connector and EB1-7... that checks out.
I checked continuity between EB1-7 and SC II1-1... and that also checks out.
But... since I needed to add that EB1-7 wire into the MKIV TT harness which did not have it originall6 I know that I made it a straight through connection with no merged splices to other wires.
So... I think I have to add Supra II1-20’s source in the engine bay (A/C connector Pin 2) near EB1-7 or nearer to the SC II1-1 connector.
And then, if I have analyzed this correctly, that circuit should work again the way the SC300 chassis wants it.
Does this sound about right?
Further edit:
I just tested continuity between the the A/C connector Pin 2 (A/C Lock Sensor) and SC body plug II1-1 and I got continuity. I unwrapped the wires for SC II1-1 and confirmed that I actually did include a splice for both the EB1-7 wire and the A/C Connector Pin 2 wire (aka A/C Lock sensor aka Supra MKIV II1-20).
So as far as I can tell, I wired that entire circuit correctly?
The only remaining thing I can think of that might cause this issue with the SC’s Ambient Temp Sensor circuit is if the lock sensor inside my A/C compressor has gone bad. If that is the case I guess it would be time for a new A/C compressor. The one I have is a reman that is several years old now.
I’m buttoning everything up for now and will sleep on all of this.
Thank you for this! I was able to cancel my A-1 Cardone re-manufactured PS rack order and I bought a reman assembly from a Lexus dealer. I had previously thought Lexus *only* sold new ones! Along with it I also ordered the three parts in the quantities you detailed.
After seeing a reman PS rack last a mere three months in my mother's LS before it blew out two days ago I will only go with a rack from Toyota/Lexus or with a personally performed or comissioned rebuild such that you did with your SC.
I didn't think to try this before but I was able to confirm that the compressor can be made to come on and stay on by turning the temperature dial to the left until the display shows the "COLD" setting. This has to be a function of the A/C computer that will bypass input from sensors that help it regulate a specific temperature.
So now I know my A/C wiring is sound enough to allow for basic function. Now I just need to confirm if I did anything incorrectly or if my Ambient Temp Sensor (A/C Error Code 12) or A/C Solar Sensor (A/C Error Code 21) is the issue causing the A/C computer to suspend compressor function unless I switch the dial to the full "COLD" setting.
I also suspect that the front accessory pulley squeaking may be from the old A/C compressor. The noise subsides some of the time but always rises in volume with rising engine RPM.
Aside, even on full cold my A/C currently puts out less than optimal cold air. It probably needs a check anyway. If the squeaking would be resolved by a new magnetic clutch then it's probably also time for a brand new Denso compressor and drier.
.....
I think I've figured out how to wire in my Mishimoto controller/relay for the TT auxiliary electric fan to automatically kick on that fan whenever the A/C magnetic clutch is engaged:
The A/C compressor connector's Pin #4 is the for the A/C magnetic clutch which comes from SC EB1-1... and which feeds from there into the magnetic clutch relay at Pin 1. On the other side of that relay is the circuit that is activated by the 40-Pin ECU connector ("A") at Pin 23.
So I think the Mishimoto fan controller's override +12V relay trigger wire can be spliced into the wire at SC EB1-1 and then that electric fan should activate whenever the Lexus/Toyota wiring/control for the A/C clutch tells it to turn on... and it should deactivate whenever the Lexus/Toyota wiring tells the A/C magnetic clutch to turn off.
Edit: As it turns out, I was actually correct the first time when I had guessed that the Supra II1-10 wire was actually intended by Toyota as an A/C Mag Clutch +12V trigger for an electric fan relay. In the case of the Supra MKIV, this wire went into that car's specific "A/C Amplifier" computer/circuitry... which presumably sent the appropriate signals to the MKIV TT's dual relay system that allowed the auxiliary electric cooling fan to be activated and deactivated by either a temperature switch sensor in the lower part of the radiator or by means of the A/C compressor's magnetic clutch being energized.
Here is why:
As you can see (and now I know after having studied these Supra MKIV TT wiring diagrams further) the square four-pin connector that goes onto the A/C compressor uses only three pins (as pointed out by Gerrb in a post above). On Pin #4 the wire goes to Supra EA1-1 (which is the same as the SC's EB1-1) and this wire goes to TWO places: to the A/C Magnetic Clutch Relay... and to Supra II1-10.
Then looking at the next diagram below in the Supra MKIV wiring TSRM which follows the path of those wires, we see where the A/C compressor gets its signal request from the 2JZ-GTE ECU.
Since the SC's HVAC system works a little differently I am only showing the diagram below for reference just to see where the wiring paths go on the Supra MKIV's HVAC.
Now normally this II1-10 wire is not needed for an SC300 to have working A/C. You don't need it, BUT... it now becomes very handy as a +12V A/C mag clutch trigger for an aftermarket electric fan relay controller that has a +12V manual override wire.
Previously I had this hooked into a temporary manual switch to turn the cooling fan on and off whenever I used the A/C but wiring my fan controller's override wire to Supra II1-10 in fact does allow the A/C system to kick that extra TT electric radiator fan on any time the A/C compressor turns on.
In a hot climate in the summer with as toasty as a GTE engine bay can get this will keep the A/C nice and cool
... On my setup, Mishimoto U18NPT electric fan relay controller's circuitry is set to turn the extra electric cooling fan whenever the temperature sensor in the radiator that runs to it reports that the coolant is too hot (@195F or @212F... I have to verify with them what the default value is set to in case minor adjustment is needed) and it will turn off whenever the coolant temperature has lowered below that threshold.
Edit: Revised this post to reflect that I was in fact not correct in assuming the Supra II1-10 wire that joins to the A/C mag clutch pin 4 and EB1-1 was intended as Toyota to directly activate the electric cooling fan any time the A/C compressor is on. For factory Supra TT's this was handled by a single-mode A/C high pressure switch which activated one of the two electric fan relays that come standard on Supra MKIVs.
So my use of this wire does work to add extra cooling... but this is not functioning as Toyota intended it to and instead of only turning on the extra cooling fan when the A/C system reaches a high pressure it just keeps the fan on any time the A/C compressor is turned on.
If possible I plan to revise this to better mimic the factory Supra TT A/C cooling configuration.
.....
The new power steering rack arrives today. The Figs rack bushings came in yesterday.
I haven't received word back yet from Yellr to lock in a special order on a replacement plug and play harness for their Yellowbox speedo corrector and now my speedometer rarely works at all. Priority today will be to jack up the car, pull out the old Yellowbox harness from the transmission tunnel and repair any damaged wires. Then, after plugging the repaired harness back in I will know if the issue is the Yellowbox unit or the Marlin Crawler screw-on mechanical speedo drive to VSS adapter that is the issue.
I did confirm it works but only when I turn the temperature dial to the full “COLD” setting. I put bright flashlight onto the sun sensor (I had tested the auto headlight sensor previously by mistake) and confirmed that I have no A/C code 21, just a code 12.
I checked all my wiring for the Ambient Temp Sensor circuit and it all seems to be fine, wires coming from the sensor to the EB1 connector included. I think that sensor is okay because it worked prior to removing the 2JZ-GE engine.
I’m not sure yet if the issue is a wiring mistake in that circuit or a bad sensor. The system works although with a tired old compressor but it just won’t allow the mag clutch to be engaged unless I have that dial on COLD due to the code 12.
I’m going to investigate again soon. Just been preoccupied with some other electrical issues. I had to relocate a ground for one of my HID ballasts and today I’m getting under the car to pull out my VSS corrector harness for repair and to determine if any damage to it or a bad Marlin Crawler VSS adapter is the reason I have no speedo signal.
I’m also looking at where I want to splice a single wire weatherpak connector into the A/C connector’s Pin 4 wire so that I can trigger the Mishimoto fan controller’s +12V override wire automatically any time the A/C is turned on. I think that should be right since that is the mag clutch power wire that the ECU acivates via the mag clutch relay.
Tomorrow I take the car in to get the steering rack replaced and hopefully to identify which pulley is squeaking from full cold startup.
The car is driving well though! 130 miles so far. Only 370 to go before I’m out of the break-in period
Thank you!! It’s a good feeling. From where it was to where it is now... kind of unbelievable Only a couple of bugs left to work out and a rear end rebuild.
Did you end up buying those piston wrist pins you mentioned the other day?
yes I did so I can throw anything on that engine and should hold up . At high RPMs , as the rods pull and push those pistons , weaker / smaller wall wrist pins can snap .
look how stout the Boat Anchor Wrist Pins are as I laid them side by side with the stock CP Piston wrist pins
^^ That's nuts! Though I am sure they are strong as designed with a good alloy I wonder why CP specified such hollow wrist pins when clearly they could have made them as stout as the other set you have there. The difference is huge indeed! These will go into one of the 3.4L stroker blocks, correct?
Remind me, please-- what fuel type are you planning to tune your high boost modes for? E85 is plentiful near you, correct?
all my toys are flex fuel ... fill up whatever you have around and let the ECU take care of the tune based on Ethanol Content . Mostly I use E85 since I have two stations within 3 miles radius
yes those are the wrist pins you get with CP Pistons , thinner wall pins 0.150" . You will have to order and pay extra to get their .200" or .250" wall pins. The one I just got from Real Street Performance are 0.300" . Thinking of building a high revving 3.0 engine . Forthe 3.4 stroker of Red Mamba , I am only using 0.250" since you don't have to rev it so high .to get what a 3.0 engine can get.
^^ So you'll fortify the lower rotating assembly at the stock displacement for higher than stock piston speeds and instead concentrate on building up your 2JZ-GTE VVT-i cylinder head for high rpms? That will be awesome! I didn't realize you're running all of them on flex fuel ECUs, just the most heavily tuned I had thought.
Lately in reading the news I learned that we may begin to see more influx of E15 at the gas pumps. Not sure how that will play out or how the trend of how blender pumps will be configured so as to still be able to get E10 91+ octane fuel. And it probably depends on the region. But still... if E15 91-93 octane becomes a common thing with it being harder to get E10 91-93 in coming years I would guess I'd need to convert my SC to flex fuel as well. Hopefully this would not be the case. E85 fuel is awesome but E15... not so much and especially concerning for old car fuel systems that have never been upgraded for flex fuel.
^^^ you seldom see fully built 2jzGE . The market for SCs just drive me nuts... there is non so I might as well build a GE vvti on the 93 5 speed whenever I get all the parts I need.
high compression loves E85 so it is just fitting that the 2jzGE vvti build be on high ethanol content.
It's sad to keep hearing evidence that this is how the market is for SC's :/
I'm very happy to have mine to use and enjoy and to have got it set up the way I always wanted it to be. I did wonder if the influx of Soarer Z30's might affect the SC market.
The 10.0:1 compression VVT-i on E85 will do quite well! And what ECU and injector system will you give that car? And will you keep its W58 transmission or use another one?
10-04-18, 05:54 PM
It's up to 85 miles on the break in. Only 415 to go! SouthBend says they want 750 miles to break in their clutch but I don't plan to do anything silly with the car before 1200 miles anyway.
Zero regrets having a 4.27 Torsen LSD rear while I was NA for many years though. Perfect for the NA 2JZ-GE's powerband, just not good for a GTE's powerband. 1st and 2nd are gone though MUCH more quickly than ever before and are now just too short of course since the engine makes so much more power and torque much lower in the rev range.
so I might as well build a GE vvti on the 93 5 speed whenever I get all the parts I need.