ecu are they interchangable

[chris frizzell]

hi fellow Zers can i pick anyones brains i have a 280z and having troble with my efi . got power to the ecu and power from the injectors back to the plug so thinking ecu knackered . my question is my car has a later 280zx engine in it dont know what year .the ecu is a 1975 one fitted to the car but do i need one to match the new engine or are they all the same ie interchangable loads on ebay but different years . will try to find what year engine is from number thanks for any thoughts chris .ps do these cars alway fight back right to the end of finishing or is it just me

 

[jonbills]

I wouldn't think the engine being later would be a problem.
I think your best bet is to download the FSM for your car/ecu and work through the diagnostics.
http://www.xenonzcar.com/s30/fsm.html

 

[Mr.F]

Using a later 280ZX ECU would imply using the matching engine loom.
280ZX UK ECUs and looms fall into two age categories - 79 to 81 and late 81 to 83. Within each there are auto and manual variants.
If you can date your donor car then I can advise on relevant part number(s).
Alternatively you could ditch Nissan and go for an aftermarket programmable ECU e.g Emerald.

Sent from my SM-G950F using Tapatalk

 

[chris frizzell]

thanks Mike where can you get these ecu from and do they require additional wiring or a simple plug in to the existing loom . I can get a second hand ecu fro anything fron £50 to £150 but run the risk off it being a dud very close to finishing the car but the thing is having starting problems apart from that only a little bit of the intierior to finish .apart fron the heater cock but may by pass so i can drive it any help always greatful chris

 

[Mr.G]

thanks Mike where can you get these ecu from and do they require additional wiring or a simple plug in to the existing loom .

Aftermarket ecu eg http://www.emeraldm3d.com/ . Any aftermarket ecu for these cars will require additional wiring and possibly dropping resistors as your injectors would be low impedance, sadly not just plug and play and then will require dyno time to get a map so she's running properly.

If you google Bosch L Jetronic troubleshooting you'll find lots of pages to help you troubleshoot, I've not heard of an ECU going so hopefully may be something else that's a simple fix.

 

[chris frizzell]

thanks just at a loss of why it wont start . i have had it running fine and when it started to strugel to fire cranking for a long time but now nothing as i said its got power through the relay to the ecu plug and i have power from the injector plug back to the ecu plug the only break in the cercuit i think is the ecu itself will try it test that if its possible any more info would be great thanks chris

 

[Huw]

Hi Chris

You would be better off looking through this manual first. 280Z/ZX Electronic Fuel Injection Guide (covers 280Z also)

I would say its unlikely to be an ECU fault (but happy to be proved wrong and eat them words), more likely a fault in one of the many other components in the EFI system. Its quite a simple system to fault find, its not a complex fuel injection system by any standard.

The ECU for the 280Z/ZX is quite a dumb piece of kit, its non programmable and hard wired. It is mostly solid state, no IC's so the ECU its quite robust.

A simple thing like a vacuum leak, faulty temperate sensor, cold start valve or even poor connector will stop it dead in its tracks. its worth using the faultfinding section in the link above.

Huw