1977 280Z ECU Location?

[SilverSurfer]

Hello all!

 

I have a 1977 280Z and I want to check the ECU ... but I don't know where it is! Can someone tell me where to find it?

 

Also, what's the difference (and location) between the Transistor Ignition Unit Module and the Ignition Control Module? Isn't the Transistor Ignition Unit Module under the dash on the wall on the passenger side, near the fuse box?

 

Thanks for any help!

[Zed Head]

It's right next to your left leg when you're sitting in the driver's seat.  Behind the black plastic kick panel.  Three screws.

[Zed Head]

 

Also, what's the difference (and location) between the Transistor Ignition Unit Module and the Ignition Control Module? Isn't the Transistor Ignition Unit Module under the dash on the wall on the passenger side, near the fuse box?

 

Same thing.

[siteunseen]

Ignition unit

 

[SilverSurfer]

Thanks everyone. I appreciate it.

 

The reason I asked about the difference between a Transistor Ignition Unit Module and the Ignition Control Module is because of this:

 

Listed as a Transistor Ignition Unit Module for a 280Z up to 1977:

 

Listed as an Ignition Control Unit for a 280Z up to 1977:

 

These both look very different to me.

[black gold man]

First one with plug is for 1978.

If you need one for 77 I have one to sell.

Edited June 18, 2015 by black gold man

[Zed Head]

Yes, the plug was used in 1978.  I think it was also used in 1974, on the 260Z (maybe not the same wiring, but still a plug).  But in between, the screw terminal block was used.  With a wiring diagram you can make any of them work.  I used 1978 module in my 76 for a little while.

 

Note though, that some modules have two ignition circuits, one to advance the timing while cold.  It's not super important, the engine will run fine once warmed up with any of them, but idle speed will drop for a short while between cold and warmed up if you don't have the advance feature (see Chickenman's recent posting on dual pickup phasing).  Barely noticeable if you lose it, but nice if you can keep it.

[SilverSurfer]

Thanks again for the help.

 

I am not certain I need one ... yet. There are a few things I need to investigate with my 280Z.

 

One is that the tach does not always work. Sometimes it climbs to around 3000 RPMs and just sits there no matter what I do (idle, race the engine, drive, etc.). Other times it seems to work perfectly. I am sure there are several things that can cause this, so I am investigating.

 

The second is the previous own had a red wire that he connected to the fuse box. He did it by exposing the wire and simply wrapping it around one of the ends of one of the fuses in the box. At first, I thought this was to the stereo/CD player (which does not work) as I remember doing stuff like that back in the 70's and early 80's. But I made a discovery quite by accident (since I had not traced the wire). I had pulled the stereo and had already disconnected the wire. When I went to start the car, the starter turned, but the engine just would not fire! I reconnected the wire (on a whim) and went to start the car. It fired right up!

I also had another strange thing happen. I had a few blown fuses and was in the process of replacing them. By accident I touched one end of the fuse to the terminal where the wire was connected and the other end to the terminal where I was trying to install the fuse. When the circuit was closed, the car tried to start! WTH? I guess I have a way to start my car if I lose my keys ...

 

I have to trace this wire, but it seems like the previous own bypassed something.

Edited June 18, 2015 by SilverSurfer

[Zed Head]

Your tachometer behavior is common.  Typically, the sticking happens when it's hot in the car, like on a hot day.

 

Disturbing that you had a "few blown fuses".  That means shorts.  Fuses should never blow.  Many people have factory original fuses.

 

Sounds like your ignition relay (not module) might be bad.  Mine was bypassed also.  Does your radio work with the key in the Acc. position?  It should.

[SilverSurfer]

 

Disturbing that you had a "few blown fuses".  That means shorts.  Fuses should never blow.  Many people have factory original fuses.

 

I had fuses blown for the hazards/turn signals and one other.

 

 

Sounds like your ignition relay (not module) might be bad.  Mine was bypassed also.

 

So this would be why the red wire is attached to the fuse. I partially traced it to the firewall, where it passes through into the engine compartment.

I just looked up "ignition relay" and it looks like a pretty easy and inexpensive part to get. Why would someone bypass it?

 

 

Does your radio work with the key in the Acc. position?  It should.

 

The radio did not work at all ... key in the Acc. position or the car fully on. But I've since removed it.

Edited June 18, 2015 by SilverSurfer

[Colbino]

I too have a 77 and noticed a red wire attached to a fuse terminal. I ALSO thought it was for the stereo, but have yet to trace it. My stereo does turn on only in ACC or further keyed position though. When I bought the car the fuse which powers the lighter was blown - this is not he fuse terminal the red wire is connected to. I'm not sure which terminal the wire is connected, but I can look if interested.