Had my son's Fiesta 1.1 Classic MOT'd yesterday. It passed, and everything was working fine. Then I washed the car and started to reverse it into the garage and it cut out. There is no spark at the plugs. Could it be the immobiliser? Sometimes the red light comes on under the clock, sometimes it doesn't. If I turn the key on and off quickly a few times I can get the red light on the right of the dashboard to start blinking. Before I start taking the air filter off to get at the distributor cap, coil, etc., is there an easy way to reset the alarm or check whether its working OK? The car hasn't been used for about 2 years, by the way. Are there any fuses that can have blown? The only thing I've touched on the car, besides a good wash, is the button on the clock to adjust the time. Cheers

 

Oh, and it has the key with the red square bit on it.

 

Yes the PATS light should be extinguished when the ignition is turned on indicating the immobiliser is disarmed, if it's still on then it's still armed. Most likely just needs a new key or more specifically the transponder in the key (The red square) this will then need programming.

Martin

 

Thanks Martin. Still not certain that its the immobiliser though. Presumably it will cut off the spark at the plugs? If I get in the car the red light on the radio, and to the right of the driver's binnacle are both extinguished. So I presume its not armed then? It only comes on if I sit in the car and operate the key on and off a few times in quick succession. That arms the car, as the alarm went off at one time. So, from the above, am I to presume that the immobiliser is working OK?
Ta
Andy

 

Yes it cuts the ignition power at the minimum, I think even the older PATS cut fuel supply as well.

Check you have +12V at the black wire at the coil with the ignition switched on.

If you do have power at coil then it's not an immobiliser issue, the most likely thing in this case is the inductive module that has given up this is mounted to the distributor this replaced the points system.

This is a MK3 Fiesta I am guessing?

Martin

 

Sorry Martin. Yes, its a Mk3 1.1, carb version, with a coil pack. I don't know much about these cars but presumably it is distributorless with ignition timed off a cam/crank sensor and via an ECU? Andy

 

Not sure about the coil pack versions but the MK2 carb versions with the same engine (Valancia) used a inducive module on the distributor, this was the most basic form of electronic ignition.

Are you sure yours is not CFI (Central Fuel Injection) this is sort of a carburettor, in either case the below would apply.

I am not up on the later Fiesta or CFI myself but would think the management would be the likes of ESC (Electronic Spark Control) opposed to EEC that the later Fords have.

Have a look by the crankshaft pulley and see if there is a sensor mounted there with a wire coming from it, this is the CPS (Crankshaft Position Sensor) this is what provides the ECU with information on engine speed, it then processes this information and gives many outputs, one will be to the coil pack which ultimatly leads to a spark at the plugs, if this is not giving information the ECU does not know this info and so no spark.

I would first check the connections are good there is normally a connector which connects the sensor to the car loom side.

If carb will be a mechanical fuel pump but if CFI then electric, this should generally speaking prime when the ignition is on at least it would on EFI would imagine CFI is the same again with no CPS info this won't happen.

Martin



Martin

 

Martin. Thanks for your help. As you suggested I looked for a crank sensor. Found a sensor on the gearbox mounting (which must sense the flywheel). The connector had been previously broken and held on with insulating tape. The connector wasn't plugged right in to the sensor. Pushed it in and the car started straight away. Was a lot easier than trying to faff around with the ignition module which is at the back of the engine. Have now superglued the sensor and plug together (if the sensor needs replacing, the connector needs replacing anyway).
Thanks for your help. Much appreciated.
Andy

 

No problem, glad shes running again, it's actually quite a modern design as all newer cars use the flywheel, you are correct they sense the flywheel there is a period in the flywheel which the sensor can sense, this represents TDC (Same principle to 36-1 crankshaft pulley older cars used) If it is the sensor side connector then a new sensor would have this, but if it's the car loom side connector which from what you saying it sounds like then it's a little harder and the mod you have done will suffice.

Martin