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Discussion Starter · #1 ·
Did a 2jzge swap [donor car was a 1994 SC300 with an Auto transmission] in to my 1985 Celica Supra with a 5spd transmission, plan on doing a write up on that experience later.

My issue is while driving, the car won't go past 4,000 rpms.

From what I understand I need to get 12 volts from the STA wire to Pin 77 and 76 during crank... I'm only getting like 10.46 volts during crank

made my connection to the STA wire in the steering column

Is there a better place for this connection so I can get 12 volts during crank?

[pics for reference below]

Steering column STA connection
Motor vehicle Bumper Automotive lighting Hood Electrical wiring


STA jumper, Pin 77 & 76 (tied together for testing)
Circuit component Electrical wiring Electricity Gas Motor vehicle

Circuit component Electrical wiring Audio equipment Computer hardware Cable


10.46 volts
Vehicle Motor vehicle Audio equipment Gauge Measuring instrument
 

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Discussion Starter · #3 ·
Thanks for the response!

I have have been running it with STA and NSW (pin 77 & 76) connected and grounded to the chassis for the last year, then I got that itch to "fix it" so I can go past 4,000rpm under load/driving.

there were no check engine codes originally, when I connected the STA wire to pin 77 & 76 I get rapid flashing, I looked that up and it means no issues.

I suppose, I will be checking connectors and wired connections this week
 

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Discussion Starter · #7 ·
I'm using the auto ECU that came with the engine

when the swap was originally done nothing was done with the STA or NSW, they were connected together and grounded because it made the car run better. Car has always had the 4,000rpm limit when driving. When parked and not in gear the car will rev all the way up to 7,000rpm with no issues.

I searched various toyota, celica, supra and lexus sites seeing what other folks who had this issue (2jz in limp mode, not reving past 4,000rpm etc..) were doing to fix it.
Most common answers were:
1. buy a standalone ecu
2. power the pin 77 with a STA source (for an auto ecu) leave pin 76 untouched or connect it to the STA source too...
3. use a manual 2jzge ecu (I'm assuming its not as picky as an auto ecu)
4. replace/rebuild ecu
 
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