Technical 93' starting issue

[SmellsLikeEspresso]

Hey,

I daily my 93 panda cabrioni. Today I went to start it and encountered some weirdness.

What normally happens:
- I get in the car
- I tap my immobiliser key, the immobiliser light goes off telling me I can start
- I turn the car over
- It runs well

What happened today:
- I get in the car
- The immobiliser light is already off
- I turn the car over
- it runs for a second and cuts out

Now regardless of how many revs I give it or anything else it cuts out in exactly the same amount of time.

I've unplugged and replugged the ECUs and now the light for the immobiliser comes on as normal and goes off when I tap it.

I hear the fuel pump if I turn the ignition but don't turn it over. I hear a relay click in the engine bay after the pump has primed.

What do I check next? Am I missing something obvious?

 

[ZaphodB]

I'd try disconnecting the battery, leave for 5 then reconnect cleanly.

 

[SmellsLikeEspresso]

Thanks for that. I tried this today and no luck. Still the same.

What's strange is it starts so well and smooth, then cuts out right away. Very odd.

 

[ZaphodB]

Gotta be immobiliser related ... is that an aftermarket one ?

 

[SmellsLikeEspresso]

It is yeah. I tried following all the cables back yesterday to see if something was loose but all looked okay.

 

[ZaphodB]

It is yeah. I tried following all the cables back yesterday to see if something was loose but all looked okay.

I think you're gonna have to revert the car back to factory (i.e. remove the immob) , confirm the engine starts... and then work out if it's a defective immob or simply wired wrongly

 

[SmellsLikeEspresso]

So I took the dash out today to start tracing the cables for the immob and thought I'd try starting. Today it will turn over, build up to a start, and cut out right away. Battery and spark is good, I wonder if it could be a pump on the way out.