Technical No spark

[YosemiteJam]

I am dealing with a Fiat Doblo 1.6 petrol 76kw, year 2003 that is unable to fire up.
It arrived with the problem of being wired in such a way as to be switched on constantly. It couldn't be shut off with the ignition either. I found that it was wired in some wonky way that allowed the car to fire up after removing the battery terminal and putting it back on. Once it fired up, however, you'd have to shut it off by putting it in high gear and letting off the clutch.
After removing those wires I could shut it off with the key but I no longer have been able to start it since it has lost ignition spark.
I changed the ignition switch- nothing. Then I changed the crank sensor with no result.
The pump is priming and there's fuel getting into the cylinders but there's no spark.
I tried to hunt down some ecu ignition feed wires but since I don't know which ones I am supposed to be looking for, I was unsuccessful at that.
I'm obviously at a loss.
Any suggestions?
Thanks.

 

[the green vanper]

Hello,

just a first thought: immobiliser?

 

[Mike1alike]

Yes, Immobilizer is my first though too.
Does the immo light on dash turn off?

 

[YosemiteJam]

Yes, Immobilizer is my first though too.
Does the immo light on dash turn off?

There's no immobilizer light on the dash, but then the dash gauges don't work properly for some reason.

 

[Mike1alike]

It should be first when you turn ignition on. Then it should go off in 1-2 seconds.
Do you have a diagnosis tool? Can connect to check for errors, see immobilizer status?

 

[YosemiteJam]

It should be first when you turn ignition on. Then it should go off in 1-2 seconds.
Do you have a diagnosis tool? Can connect to check for errors, see immobilizer status?

No, I don't have a diagnostic tool. Is it possible that the battery (assuming there is one) inside the key might be dead?

 

[Mike1alike]

No, there is no battery inside key for immo. Only a chip with code that ECU reads everytime.

 

[the green vanper]

I'd say the weird wiring was made to bypass the immo. Once the wiring was done properly, the immo won't allow to start.

This can be done with MES or at the dealership. Copying is not the solution as you don't have the correct key.

 

[YosemiteJam]

I'd say the weird wiring was made to bypass the immo. Once the wiring was done properly, the immo won't allow to start.

This can be done with MES or at the dealership. Copying is not the solution as you don't have the correct key.

I see. That might be the case. Odd thing is, when I wired it up the way it was it still wouldn't start...

 

[the green vanper]

I'd say it's expected behaviour. You removed the bypass, you tried to deactivate the immo in the proper way (with the key), so it knows it's locked. The cables, when attached, somehow managed to keep the immo unlocked.

I might be wrong of course, but that's how I understand how it worked.

 

[YosemiteJam]

Update. I put the new ignition switch into the old ignition barrel and, using the old key, the car fired up. Now, however, it presents with a new symptom, namely it doesn't rev up, as if it's in limp mode. I unplugged the throttle position sensor plug and there was no reaction....

 

[Mike1alike]

Update. I put the new ignition switch into the old ignition barrel and, using the old key, the car fired up.

That is great news! I missed out in your first post that you replaced ignition switch!

 

[Mike1alike]

Now, however, it presents with a new symptom, namely it doesn't rev up, as if it's in limp mode. I unplugged the throttle position sensor plug and there was no reaction....

Would be useful to get yourself an ELM tool and MES to see what's going on there.
Is the throttle cable operated?

 

[YosemiteJam]

It is electronically controlled. There are four (as far as I remember) wires going to the ecu. When I jiggle the ecu connector, the rough idle smoothes out but the revs stay the same...

 

[the green vanper]

Yes, a FIAT compatible scanner seems to be necessary at this point.

However disconnecting the battery for like 30 minutes could be a good starting point - there is a possibility the errors will clear. For some time And a fresh set will eventually appear

 

[YosemiteJam]

I took apart the plug and found that some of the connectors are kind of loose.
I searched for a plug but no luck so far.
My next option is to get some new of those tiny terminals and replace them individually.
Do you, by chance, happen to know what type they are?