123 ignition wiring

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Henrik

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I have just installed a new 123 Ignition distributor in my D-jet, but not possible to start. There is a single white wire (has stamped 41 on it) that was connected to the old distributor, but the manual doesn't say anything about it. Should it be connected somewhere else to get a signal to the ECU??
 
After some research I found that the single white wire activates the main relay via the ecu. If the 12V signal from the distributor disappear (engine stopped) the relay opens and the fuel pump stop running (at least this is my theory).
I connected the white wire to the + pole on the coil and the engine started immediately. Everything is fine except for the safety feature that shut down the fuel pump in case of a crash. Any solutions to this anyone?
 
You have the early harness- single white wire connects to same place as green wire from ignition switch at dropping resister.
Now you have no points and no dropping resister- the white wire which provides switching power to the main relay at pin 86 is hot whenever the key is on. You should connect to pin 15 at coil (green wire)
Pin 30 at relay is battery power from starter at pin 30.
Computer is activated by pin 87 at relay to pins 16 and 24 at computer


BTW- no on your theory. Sorry.
 
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Now that your engine is running, confirm that your actual timing matches your 123 curve by checking with a timing light.
 
OK, my first thought was that the original wiring (single white wire- to distributor) had something to do with a safety feature, but obviously not:
sfdon said:
the white wire which provides switching power to the main relay at pin 86 is hot whenever the key is on.
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Good to know! Thankś Don.
White wire is connected to + on coil (pin 15) and everything is working well except for one thing. I had hoped that the 123 ignition would give the engine more boost from idle -- better acceleration, but it is like it was with the old distributor. The engine has only been running a fem kilometers but I had expected more power and instant reaction from idle an upwards. Itś very different from other cars. Is there any adjustments that can be done that might solve this?
Stevehose said:
Now that your engine is running, confirm that your actual timing matches your 123 curve by checking with a timing light.
Click to expand...
The 123 timing seems to be almost spot on according to my timing light, so this should not be the reason for the slow reaction when running in a low rev. I know that the potentiometer at the ECU is turned to minimum CO%. Can this be an issue?
 
Your computer determines fuel at load- not your distributor.


What is your timing at idle? at 2000 rpm?
 
Henrik said:
The 123 timing seems to be almost spot on according to my timing light, so this should not be the reason for the slow reaction when running in a low rev. I know that the potentiometer at the ECU is turned to minimum CO%. Can this be an issue?
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I don't know about that, but you can go ahead and turn your distributor so that it matches exactly the same.
 
sfdon said:
What is your timing at idle? at 2000 rpm?
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Measured with vacuum advance the timing at idle (1000rpm) is 8 degrees
at 2000rpm it is 12 degrees. This is done after the 123 was properly adjusted according to their instructions.

Shot this video a while ago.
Sounds very potent with a SS steel exhaust. Hopefully a fine tuning will add some power to the engine so it can match the sound:)
 
I would look at how that CO2 potentiometer operates. Is it possible that the potentiometer might tell the cpu to retard timing in certain parts of the rev range so as to minimize CO2 emissions?
 
It should be 22 degrees at 1700 rpm.

Chris Macha




Try 13-15* at idle and 22* at 1700

your timing needs to be advanced some. No need to change the curve in 123 unit- just rotate distributor clockwise 1/4" and then check your timing for 22* at 1700 rpm
 
Ohmess said:
I would look at how that CO2 potentiometer operates. Is it possible that the potentiometer might tell the cpu to retard timing in certain parts of the rev range so as to minimize CO2 emissions?
Click to expand...
My understanding when reading the workshop manual is that the potentiometer only adjust the fuel volume. It was turned to minimum when I started the engine for the first time and did som test runs in the nearby streets. I have now turned it to about 50% and the engine
runs better and is more responsive in my opinion. I don't have any instruments to measure the CO volume so the adjustments must be based on "engine running as smoothly as possible" as the manual describe it.
After turning the potentiometer the idle/air screw had to be turned several times clockwise to reduce the idle.
I will go on with the timing later today and try to get it to 22º/1700rpm.
 
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