Hi Michelle,

When you say unreliable starting can you expand a bit. When trying (and failing) to start it does it turn over quickly or slowly?

For the engine to start you need several things:-

1. Air fuel mixture - Is the air intake clear? When turning on the ignition listen before cranking to see if you can hear the fuel pump run (hum/buzz) for about 2 to 4 seconds and then stop. It stops when the fuel rail is up to pressure (unless fuel filter blocked) which is good.

2. Compression - The fuel/air mixture needs to be compressed in the cylinders. Provided the engine turns over quickly enough during starts this can be taken for granted as your problem is only intermittent.

3. Ignition - We need a spark. Mace has mentioned this already so I'll move on.

4. Somewhere for the result of all this to go - If the engine fires briefly but then dies, it could be your catalytic conveter has broken up and is blocking the exhaust. Best way to check is to disconnect the exhaust from the manifold and try again - be prepared for loud noise and don't run for long as very hot gasses will be venting in the engine compartment so risk of fire/melting etc so take obvious precautions.

Always try what's easiest first - check for loose electrical connectors. Also check your battery is fully charged - I've known batteries to be good enough to spin an engine over well but leave insufficient for the ignition system to function.

Really hope this gives you someting to go on. Let me know how you get on.

Regards
SixFingersMike