Editing Forums/Z31P/z31-repairs-forums electronics/1984 na edu problem

{{ForumImport
|op_user=BrianH
|op_date=2017-10-13 15:23:01
|post_count=4
|archive_url=/Z31performance_archive/forum/z31-repairs-forums/electronics/537425-1984-na-edu-problem.html
}}

'''BrianH:''' <small>(2017-10-13 15:23:01)</small>

I picked up an 84 na basket case as a parts car. I wanted to get it running to see what was good and what was bad.

After getting it to start, and run poorly, and spending hours cleaning connectors and testing sensors, I put a spare ecu in it. Miraculously, it starts and runs very well.

problem is, the ecu that runs good is an 88 na federal. I think there may be an incompatibility with the 84 o2 sensor, and the 84 injectors.

I'd like to drive it while I build my real car, so I need to source an ecu. Any advice? Rock auto has an a1 cardone remanufactured for 200$. Anyone use one of these and have good or bad results to report? Is there a better source?

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'''Z_Karma:''' <small>(2017-10-13 18:27:27)</small>

[http://redz31.suomiz.net/pages/fuel.html http://redz31.suomiz.net/pages/fuel.html]

You're OK on oxygen sensor compatibility, But you're using a high impedance ECU on low impedance injectors, you could potentially be sending them too much power and eventually short them out.

Drop resistors are the usual modification for running low impedence injectors on high impedence ecu's.

[http://redz31.suomiz.net/pages/fuel/resistors.html http://redz31.suomiz.net/pages/fuel/resistors.html]

(here is a archived version with the images intact)

[https://web.archive.org/web/20090224223710/http:/redz31.net/pages/fuel/resistors.html https://web.archive.org/web/20090224…resistors.html]

That's assuming you are running stock na injectors and they haven't been swapped for some unknown injector by a PO.

I wouldn't bother with a re-manufactured ECU for a parts car.

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'''BrianH:''' <small>(2017-10-13 18:39:25)</small>

I read about the injector difference, and just ran it for about 30 seconds just to test. I have very rarely experienced a bad ecu on these cars, but was running out of other causes. I have a JWT 4 bar for the real car, but it won't help here. I just ordered an 87 na ecu off ebay. Hopefully it will work ok.

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'''bonfire79:''' <small>(2017-10-14 06:39:32)</small>

if you end up needing another ECU, get with Steve over at [http://www.300zxpartsforyou.com www.300zxpartsforyou.com]

he has many ECUs all stock all years.

Bon