Crown ECU Engine Loom

[Quadcob]

I am just about to modify the engine loom using Kdog's drawing. There are a few things I have questions about.

1. The Crown uses a fuel pump speed relay for 2 speeds. I was going to just use a single speed. What are the pros and cons of these different systems?
2. The exhaust control flap. What does it do, where is it located and do I need it?
3. Any reason to install the exhaust gas temp lamp?

Thanks

Warren

 

[Zuffen]

Quadcob,

1. The advantage of the twin speed pump is it is quieter in cruise and idle. it will also make the pump last longer. To make it work is a couple of relays and the large finned/silver resistor that is mounted in front of the fuse box.

2. Don't worry about the control flap. I think it is part of EGR which Crowns don't have. I terminated and insulated that wire.

3. Exhaust gas temp light is another I never found. I have looked for a sensor/probe to no avail. Unless it is mounted back with the Cat (which doesn't come with Crown front cuts). I terminated this wire as well.

When doing the dual speed fuel pump I used the Soarer diagrams in the tech section to see how the factory wired them. Study the schematics and draw out what you are trying to do and it becomes much easier.

There are literally 12 wires to connect to get the engine to run. Throw in a few more for temp and oil pressuere and you are done. This isn't a half hours work but an easy day for a reasonably mechanically aware person. The biggest job is getting rid of all the wires you don't need. I spent days )literally) trying to utilise the Crown fuse box until I realised a small fuse board and a few relays would see it all running. The Crown fuse box is a nightmare to work with. Some earths go to 12 different places.

One note the ECU has 4 plugs. You only need to use 3. The small (separate) plug is not used on a manual conversion.

If you get stuck put up a post there are plenty of us who can assist.

 

[Quadcob]

Rod,
Thanks for the information. I was going to use a smaller fuse box(it was mentioned on this forum that a 180 SX fuse box would do the job) and a fusible link box from a EF/EL Falcon. The loom looks as though it will be a time consuming job.

Warren

 

[Zuffen]

On my swap I had to swap the alternator across to where the air co compressor was.

I simply swapped the alternator wiring over and integrated it into the loom. I used the Crown fusible link (I had it and it was already attached to the loom) and wired that into the original vehicles loom.

The fuse board I used has provision for 8 modern spade fuses. I am using 7 of the spots. Not all of the 7 are to run the engine.

There are only 4 relays needed, 2 if you delete the twin speed fuel pump.

As I said sit down draw it out and draw the circuit you need for the fuel pumps (you don't need to use the correct symbols) so YOU can understand it and it will go together easier than you think.

Of interest where are you located?

 

[400ZED]

Where is Kdogs diagram you speak of.
I am about to start wirring a crown and don;t have the diagrams.
Can you point me in the right direction.

 

[Zuffen]

Stirling,

Look in this section on 15/8/04. That is the date of the last post on this thread.

It is not so much a diagram of how you integrate the engine loom with your swap vehicle. It is more the pinouts for the ECU & ECT with wire colours.

It is very self explanatory. Even I followed it and got the thing to run.

 

[KDog]

Ditch as much of the loom as you can. And make your own relay/fuse boxes or use the original one for the vehicle. It will make it a much cleaner and easier install.
If your using an aftermarket ECU then ditch all of the engine wiring and start from scratch.

 

[Quadcob]

Started stripping unwanted wires from the loom. Only difficult part is that some of the plugs are a bit reluctant to come apart.

Rod
I live about 50K's west of Brisbane.

 

[Zuffen]

Quadcob,

I suggest you PM 400ZED you guys are doing the same thing at the same time. You may be better off helping each other do each wiring job. You are both (basically) Brisbane based.

Two heads are better than one.

 

[Quadcob]

There are a couple of pieces of equipment that are on the motor that I can't identify.
On the throttle body, connected to a butterfly, is what looks as though it could be a small motor(traction control?). The butterfly is connected to throttle sensor 2.
There is also a sensor in the water port adjacent to the water temp sensor and water temp sender which is brown in colour. This looks as though it is wired back to a fuel device underneath the top part of the air plenum. There is a green wire and black wire with a white strip going to them(cold start injector?).
Can anyone help identify these items.

Also there are a number of wires going to diagnostic plug on top of the motor that appear not to be part of the ECU loom and go to other parts of the vehicle. Am I correct to say if there are wires that do not appear on the ECU drawing and they appear not connected with any components the wires can be terminated.

 

[Zuffen]

The additional butterfly is the trac control. Disregard it unless you actually want to run it.

The brown sensor is used to sense water temp for the air conditioning. Another you can ditch. The wires from this unit run under the plenum and into the loom at the rear of the engine. The cold start injector is wired separately but through the same loom.

Don't worry about the diagnostic plug. Just leave it there and all the wires connected to it.

 

[Quadcob]

Rod
The brown sensor is wired in a loop configuration with the fuel injector under the plenum. The wires are green and black with a white strip. The only wire that appears to be connected to any thing is black wire with a white strip. This wire goes outside the engine loom to the fuse/relay block. This wire could be starter output to fuel relay. When the wiring looms are modified I can not see how the injector under the plenum will work(with only one input I cannot how it works normally). From what I can work out it appears on motors with modified looms the cold start injector will not work. If this part of the crown is similar to soarer it requires start injector time switch

Warren