Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 M3W doesn't start anymore

Hi out there,

my 3wheeler will not start anymore ..

I'd checked the petrol injection (with S&S proTune, seems to be ok., petrol pump is also running, I can smell the petrol when starting with sparks removed ...

So I found that the sparks (both) are not firing, I'd measured the ignition coils, seems to be ok.

In a next step I connected a DSO (Digital Storage Oscilloscope) to the input of the ingnition coil and found, that after 'ingnitgion on' the middle of the 3 cables will connected to 12V+ (thats what I expected) , but only for around 10sec. than it falls back to 0V ....

The outer cables (from my understanding they will be switched to ground by the ECU (VFI) to fire the sparks) doesn't show any ground connections when trying to start the engine (starter is running) .....

Any Idea?

Has anyone a wiring diagram of the ignition system of the M3W ?

I'm afraid that it may be a problem of the immobilizer (from Stevens) , I would prefer to remove this completly , has anybody done that or some information about this ???

Thorsten

Check the throttle cable isn't frayed or sticking. If the throttle isn't shut the ecu won't fire the spark.

Behind the oil tank is the reset button for the impact/accident cut out. It's a black, rubber shrouded button and can occasionally disconnect for no good reason. Worth finding and giving it a press. Easiest thing to eliminate.
Good luck finding the problem.

sure ?

that's very intresting and good to know, because I'd played around with throttle position sensor (I was in doubt that a faulty sensor was the problem of my idling problems)

I'd installed it to 10% when closed (value from S&S ProTune) , what from my understanding was the default value.

Thanks , I will check that soon !

Hi RedThree,

always read about this button in here in this forum. Pressing this button doesn't change the fault situation, but nevertheless I will measure it tomorrow again - only to be sure.

Thanks !

btw. meanwhile I found (from mtwc website) a document from S&S (S&S XWedge installation guide) which includes a complete wiring diagram of the S&S ECU ...

That could be handy👍

Yes as this was what caused the only time I've had to have my car recovered.

As a quick check:

Stuck throttle - fuel pump and starter work but no spark

Inertia cutout - no fuel pump but starter works

Imobiliser active - no fuelpump or starter.

If you've reset the throttle position I'd check what the default initial value should be, or maybe try it at 0%?

If this fails you may be looking at an ECU or indicator module problem.

Is there something that can be plugged into the OBD Port to diagnose such problems?

I had the factory fitted immobiliser (toad?) and one day when out on a run the car wouldn't start. Much naughty words and a tow home
Turned out to be at that the immobiliser remote cancel dongle had failed.


I made a "bypass" plug so that at least could get mobile if such was to happen again

However, cost of a replacement dongle is excessive, so have installed bypass full time