1UZ swap into MA70 - what to keep/ditch when ordering the harness from Tweak'd...

MoparMarq

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#1
Am in the process of getting the engine prepped for the swap. It's out of a a '92 SC400, complete from stem to stern.
What should I keep on the engine and subsequently on the harness when I talk to the fellows at Tweak'd.
Obviously will get rid of EGR.
What about Cold Start Injector? Keep or ditch? I've read some later SC's didn't have it?
I'd like to keep Idle Speed Control.
Car had Traction Control. The Supra, of course, doesn't have it, nor have ABS.
Can I ditch the Trac Control Actuator and also the Sub-throttle TPS?
And is or was there an available non-traction control throttle valve assembly to clean things up a bit?

Tried doing a search, but "1UZ" is too short a search term, apparently.
Thanks for any advice or assistance.
-Marq
 

hvyman

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#2
If staying stock egr isn’t really a bad thing to have. It’s only active during cruise.

For stock ecu the cold start injector would prolly have better start up drive ability if the ecu your using is looking for it.

The trac stuff you can delete.

The throttle if you use a non actuated throttle then you can delete everything except for tps. If you use that throttle you need to leave it.
 

Piratetip

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#3
You might want to install a new starter before putting this engine in the vehicle.
Quite a lot of parts to remove to get to it later.
Also goes for the EGR components, either replace all the parts with new or delete it.
This specific engine can have some EGR pipe cracking issues.
The parts are not easy to get to later if there are issues.
 

MoparMarq

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#4
Sticking with original ecu; 89661-24240. Was planning on new starter, for the reason mentioned. I assume it’s prudent to spend the money on a Toyota part instead of, say, NAPA. I’ve had issues with non-OEM starters before, and would like to avoid that road again.
Would new cold start injector from Rockauto be satisfactory?
Didn’t know about possible cracking with EGR pipe. Good to know, thanks, Pirate. Will probably delete EGR.
Also replacing crank and cam seals, of course, as well as timing belt and both TB idlers (and water pump). Anything else?
 

Piratetip

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#5
Don't delete the EGR if you are keeping the ECU stock FYI.

The computer will expect a certain flow of exhaust gasses into the engine.
Without EGR you can potentially cause some serious issues with fueling, A/F ratio, partial load problems while cruising.
 

MoparMarq

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#6
That worthwhile considering. With exhaust gasses expected, but not present, I assume A/F will probably be somewhat too rich, but wouldn't ECU
compensate via O2 sensor input? Or is sensor input not wideband enough?

What about TRAC? Obviously, without TRAC ECU, I can delete sub-throttle actuator, but can I also delete sub-throttle TPS without getting a 47 code?
Not really clear in Factory Service Manual that 47 code will set if TRAC ECU is not present.
 

Piratetip

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#7
A/F goes lean if uncorrected by ECU and EGR is deleted.
The ECU does have some capability to adjust and correct if EGR is deleted.
Though for this engine and ECU I do not know to what % of correction it is able to go.

IMO, it's best to keep EGR functional on a street driven vehicle.
It's upsides far outweighs any potential gains from removal or delete.

On TRAC topic, I do not know offhand.