306 wont start when cold

Post by **xantia_v6** » 28 Aug 2010, 11:37

I have a relative in New Zealand with a 1994 306xsi petrol. It often won't start when cold, or takes a lot of cranking to start. It starts fine when warm.

They have spent quite a bit of money at a garage trying to get it fixed (apparently replacing parts at random), but there has been no definite fault found.

I don't know much about these cars (not even what sort of fuel and ignition systems), so can't offer them much advice. The owner is totally non-mechanical.

Are there any common faults to be checked for?

spider · Post by **spider** » 28 Aug 2010, 12:08

Fuel pump relay although (usually around ECU in engine bay) is a thought.

Although if its only when cold my first thought is the coolant temp sensor (the one for the ECU, not the one for the gauge) , if its reading 'high' the ECU will not provide enough mixture for a cold start, but when warm will not have any effect really at all. I'm not 100% sure where it will be, its highly likely to be one of the (three usually) fitted around the thermostat housing.

This sensor is likely if you find it similar to attempting to start a carburettor engined car without any choke (ie: eventually it will go and once its got a bit of warmth its fine till the next day)