Punto not starting!

[asullivan]

I've just recently purchased a 1998 (S) punto sporting 1.2. My husband was with me so he checked all the usual docs. Mot and service very recently been done and nothing wrong when we bought it.

Since then, we've had a few times when it simply won't start. It turns over but doesn't fire (we've waited until the noise of the fuel filtering through has finished before turning the key further).

On occasions we can leave it for a couple of hours and it'll start fine again but other times haven't been so successful.

The battery works fine as we've tested the electrics and nothing abnormal shows on the dashboard lights.

I'm a bit worried about driving it now!

Any ideas?

[larsen_huw]

For an engine to start you need three things.

1. Fuel.

2. Air.

3. A Spark.

You say you can hear the fuel flowing ... so it is leaving the tank OK ... are you sure it is arriving at the engine? Some cars have a fuel filter between the tank and the engine ... does your punto? If so, when was it last changed?

Air ... this is controlled by electronic sensors from the ECU, so unless the air filter is heavily blocked (unlikely) then you can assume you're getting enough air.

Spark ... There are two things needed for a sucessful spark ... strength and timing. The fact that the car starts fine sometimes would suggest to me that the timing is ok and doesn't need adjusting. It's possible you are getting a weak spark which is boarderline for igniting the mixture of fuel and air in the engine. Check the service history to see when the spark plugs and HT leads (and distributor cap and rotor arm if the Punto uses a distributor) were last changed .... if it was more than 6 months or 6,000 miles ago, it might be worth changing them to see if the situation improves.

My gut feeling is there's a loose wire somewhere in the electrics, which allows the various sensors to deliver the correct information most of the time, but every now and again the wire works its way loose enough to disrupt the signal, and the engine refuses to start.

[rivolette]

I think larsen_huw pretty much covered everything, I'd just add that there may be a glitch with your ignition coil. Not very likely as you mentioned it sometimes starts fine, but nevertheless, it is something to consider.