irregular tickover?

Question

i have a 2.0lt ford probe which has suddenly decided to tickover at 1500 rpm then drop to 500 rpm then back to 1500 this happens three or four times before the tickover returns to normal anybody any idea what the problem might be

cheers roy

Answer 1

try replacing the rotor arm inside the distributor cap. this might have worn away and should, once replaced, cure the problem.

the rotor arm is like a dynamo that generates a spark of electricity that is then sent through the spark leads to the spark plugs.

Answer 2

NielH, it shows the last time you looked under a bonnet of a car the rotor arm went out about 20yrs ago being the prob is fuel injection and electronic ignition I would like you to show us were the rotor would be.
Any way i digress, personally I would go for a service of filters first if you haven't already, then I would check the air inlet as this has a habit of building up a bit of residue and sludge which sometimes prevents the butterfly from returning properly and can cause the tick over to be irregular, then if that doesn't work find someone with a sun tuner or equivalent so they can plug it in and tell you where the problem is stemming from otherwise you will be there a while trying to find the sensor causing the problem, if it is a sensor!!

Answer 3

Try a different garage for your petrol. Also check the connectors to the sensors for the engine management system.

Answer 4

sounds like a sensor problem sending incorrect message to the ECU

Answer 5

i have 2 probes and am in the middle of an engine swap on one too....with probes its generally sensors as they have loads lol try distributor and if not it shld be a sensor...jst gta find which one......nt as easy

Answer 6

that sounds like your ecu (cars brain) is playing up.