Fuel issues?

[Bushwhacker]

Thank you. I can stop worrying about that then

This is totally messing with my head now,
The old ECU that has no W warning light and has damage to the board from a leaking capacitor allows the engine to fire on every attempt of the key.
The engine only fires on the first turn of the key and not unless you leave it for 5 mins does the new ECU make it fire again.
Whats going on? This cant all be down to my iffy wiring? Do i have 2 iffy ECUs?

Are there any black/orange trace and black/red trace wires that are running alongside your engine's loom, not associated with the ECU plugs, that are not connected?

 

[redsunbeam]

I have one thick black/red not connected that is going to go to the fuel pump ecu. I have 12v at the +B on the diagnostic connector with the ignition on and whilst cranking. I have 12v at the fuel injectors and the ignitors also. That was a very specific question, do you have something in mind?

 

[Bushwhacker]

I have one thick black/red not connected that is going to go to the fuel pump ecu. I have 12v at the +B on the diagnostic connector with the ignition on and whilst cranking. I have 12v at the fuel injectors and the ignitors also. That was a very specific question, do you have something in mind?

I did, but you seem to have it covered.
Basically, any black/orange and black/red wires need ignition 12v.
All white/black and brown wires need to be grounded.
black/yellow need constant 12v.

Maybe it's the fuel pump ECU thats causing the trouble? I wire the fuel pumps through a relay that powers the pump whilst cranking, then switches over to constant running triggered by the oil pressure switch.

The way you describe the running for a few seconds then cutting out, then will not start for five minutes after, sounds like the fuel in the rails is being used up and not being replenished.
Are the fuel lines definitely on the correct way? What type of filter are you using?

 

[redsunbeam]

I had heard the fuel ecus have a bad reputation, so its not connected yet. One thing at a time should have kept it simple! Fuel pump is off the m-rel trigger so keeps running when the ignition is on. It sounded like fuel to me too untill i put the old ( damaged ) ecu back in and it fires every turn of the key.

 

[gloverman]

Did it run on engine start? Are you running a main relay? What is the ECU number? pin configuration?

 

[redsunbeam]

Have established that the ecu is ok, its been tried in a soarer and is fine. I am running a main relay.
The error code 15 has cleared with the addition of a pair of good ignitors, but it still wont run.
The only fault code now is 31 which is the afm. This shouldnt prevent it from starting should it? I thought an engine would run with an afm disconnected?

 

[lill daddy]

just another thing to look at... if the idle air control valve is plumbed incorrectly it will give you a afm fault code and the motor will fire for a few moments then die.. also running it in a super rich state (fouling plugs) etc it has to be plumbed after the afm and before the butterfly... let us know how you get on...

 

[redsunbeam]

Found it !
We have a RUNNER !!!!!!!!!!

 

[lill daddy]

and it was...... lol awesome news though

 

[redsunbeam]

When i metered out the wires in the loom i used a thin sliver of steel to poke in the plugs that go on the ecu so i could put a croc clip on it. The steel opened out the connectors in the plug giving me poor connections all over the ecu. Took the yellow covers off, gently closed up the connectors a little and brrrrmmmm.............

 

[lill daddy]

nice!!! it sucks when its so simple yet takes so long to find.... had a similar issue with my conversion last weekend... went over and over all the hard stuff and turned out to be the simplest thing.....

 

[samsdad]

I've made that stuff-up before and it's something you only ever do once and when you do it takes ages to find then causes much cursing swearing and gnashing of teeth. The lesson learned here and if you have access to factory manuals they also tell you this, but when tracing wiring or even testing a circuit to trouble shoot always "back probe" the plugs, by this I mean put the pin/probe in from the wiring side not the computer side. You can apply a really grotty saying to this as with many other things when working on cars as to not forget the correct way of doing things. I won't go into details but I'm pretty sure that most red blooded males can work it out.

Great to hear it runs now