Hey guy's,

Believe it or not, I still have not got the damn race car to fire up. After checking everything that had been previously suggested (and More), i put it on hold while working on other areas of the car. Now it's time to get serious......

We have tracked the problem down to the wiring of the injectors (we think)..... the car will start on Aero start, we have good fuel flow to the rail, and it is holding pressure at the rail. The injectors have been tested and are fine (Bosch Motorsport 550cc). I have had someone who knows Motec help set the CrIP, which is shown in the car firing on the aero start.

Here are the current symptoms......

1.When you first crank the car, it goes to fire...sounds very promising, but after that is basically dead until you turn the ignition off and then on again (resetting the Motec). When you try to crank after restting, it does the same, tries to fire initially...then nothing.

2. When doing the diagnostic test...... the injector will test OK for about 2-3 seconds.... then a weird message flashes on the screen. The messages says something about being unable to test due to the engine running?????? Which of course it is not.

3. All injectors have been tested while cranking, and all of them are pulsing.

The question is....are the first two symptoms related?...I think they are.

Has anyone come across this before, or know what may be causing this?

We have also tried increasing the Overall trim on the fuel...right up to 50%. The result on cranking was the same. We checked the plugs...and they did not show signs of bathing in avgas....which should have been apparent with 50% overall trim added. They did show signs of fuel getting in there, but I think this is from the initial cranking...... and then for some reason the injectors are not doing there job.

Sorry for the long post..... any help will be greatly appreciated. This thing is driving me INSANE!

Dude, I'm assuming this is the FJ....

Are you using the FJ dizzy, with the standard nissan chopper wheel as yer trigger?

Yep...the FJ it is.....

It runs the Dizzy...with a hall effect sensor. (360 degree optical - is that right?)

Hi datman55,
it sure sounds like you have an interesting problem

I have had lots of experience with Haltech and some with Motec. One of the most common problems with these systems is the earth they receive. On my Haltech we have had to run multiple earths even after being told that it's not necessary. Well it was and fixed the problems we were having. I'm not sure if this info will help you but it fixed my ecu problems so I thought I would pass it on. This all sounds very simplistic but is often overlooked.

I have some Motec mad mates, so I'll ask the local Motec guys if they can help.

Paul.

Thanks Paul,

Adding an extra earth or two certainly wont hurt anything..... will give it a try if we have no luck on other fronts.

I spoke with Motec today also, they have told me to check that the "ref" input to the ECU is not receiving any voltage during the injector test. Any Voltage on this wire will tell the computer that the engine is running, and therefore cancel the test. THe fact that it only happens after the injectors are triggered in the test phase indicates that there may me some interference or electrical "noise" getting into the "ref" wire and tricking the computer into thinking the engine is running..... this will be number one test.

Also, I have to check the resistance on the injector at the ECU end of the loom, to make sure we are not getting a large voltage drop through the loom, therefore not having enough power to drive the injector, but still enough to show a pulse on the node light.

We will check those things out first..... and see how we go from there...... Now where did I put those webers!

Mark I was going to suggest that I could swap you two fully rebuilt 40mm webers for the motec and the inlet manifold, throttle bodies etc. I guarantee it will fire first go!!!

I know it probably sounds silly but have the injector resistances been set up correctly in the setup screen.

converted makes a very good point there

mark,something that happened to a friends 1200 coupe which might be close.when he was cranking the engine,there was no power to the ignition circuit,due to a mismatch at a connector in the wiring loom.the engine would sound like it would fire,but never did.he tricked it into firing by turning the key back to start quickly,& this sometimes worked,until the real culprit was found.could this be a problem?did you have a wiring loom made up to suit the engine?you didn't say if there was power at the plugs when cranking.it sounds like you checked everything else.
bugger,you said it'll run on aerostart,so you've got spark,forget i said anything.

yo
the FJ dizzy has a wheel with 360 little holes and 4 big holes in it. It uses an optical sensor to read these holes.
I had no end of trouble making the Link EMS system work reliably with this, so I had some new wheels made, with 4 little holes and one big hole.
I hear thru the grapevine that motec also struggle to make the early nissan wheels work.

I've since discovered that autronic
autronic also make a new trigger disk for the FJ.

Just recently, we found that the very last of the FJ's, while still using a 360/4 wheel, have a completely different pickup. they give a clean trigger signal however the 4:1 wheels dont work in these.
This is the system that nissan continued with, on the CA, RB etc...
So, you can use the eary dizzy module with a 4:1 wheel from autronic

or replace the dizzy inards with those from an SR18.... (goes straight in the housing)

Give motec a call, and ask them specifically about the nissan 360:4 setup and see what they reckon dude...

T