The pink wire at ignition plug gets 9.36 volts with ignition on. When switch to run it gets 11.46. this is all with ECU hooked up. Without ECU hooked up I get 11.46 on pink wire ignition on and in run and same at pink wire at ECU plug. I was measuring the wrong wire other day when it was showing 4.90 at ECU so disregard that.
If this helps anything?

 

So doesn't it sound like I have a bad ignition zener diode?

 

Zener's on backwards. Test measuring it both ways 1st before soldering on.
I've seen switches now where some has to face one way, and another has to face other way.
So only sure way to know for sure is to place it on contacts and hold it there.
Then measure output at pink wire at ECU connector.

Also keep battery on smart-charger 24/7. Voltage is too low to operate ECU properly when you're cranking. So even IF everything is perfectly OK, ECU's dead when cranking.

 

Okay I'll try and desolder it tomorrow and flip it around. Thank you

 

So apparently I bought the wrong zener diode.
I bought 1N4730A 3.9V 1W. I was getting 6.43 volts. Turned it around and was getting 10.43.
Which zener diode do I need?

 

Battery fully charged at 13.04

 

Let’s see…

6.43v + 3.9v = 10.33v in reverse-bias direction
10.43 + 0v = 10.43v in forward-bias direction

Do these tests:

1. Measure battery power with everything OFF, volts=??

2. Measure battery power during cranking, volts = ??

 

13.00
11.65 while cranking

 

New diode. 9.75 key on.
Kill switch on run 11.65.
Still no prime.
What else can it be from all we tested?
Not diode, not pump, not ECU.
So it is a mystery apparently

 

Just to let you know before you say the diode is backwards. This is a new factory OEM ignition from Honda
Waiting for your expertise.
Thanks