Vectra wont start when warm!

[haye5]

My vectra 03 1.8 ls starts first time from cold, but when i drive it short/long distance and stop i go to start but it wont! the car seems to either not be getting fuel or a spark. i have checked battery voltage and it is 12.7 which is what it is suppose to be. the engine management light is not comming on so on fault reading. anyone else had this problem i dont want to take to vx dealer yet as i am tighter than two coats of paint!

[Big Sig]

Does the temperature gauge work ok?

[haye5]

Does the temperature gauge work ok?

Its work one day and not the next.

[Big Sig]

It could be related. If the car is hot but the ECU thinks its cold then it may overfuel and "flood" the engine so it will not start.

Could be the temperature sender in the thermostat housing imo.

You need to see when it fails to start if the gauge is working or not. Mind you I am not sure if it has more than one temp probe for the engine temperature.

[haye5]

thanks i will check the thermo, there is no smell of fuel from the engine bay, so dont think its flooding.

[Big Sig]

I take it you have checked the plugs already etc?

[haye5]

no i have'nt checked the plugs as i found it strange if it was the plugs it would satrt at all, i aslo thought it might have been a the coil pack but again if it was it would'nt start at all. thought i would put on a post to see if anybody had the same prob to save me time.

[Big Sig]

Not true. Sometimes components break down when hot but are ok when cold. IRS worth looking at them when it's free.

[Das]

Might be worth while changing the spark plugs, maybe something simple like a cracked spark plug.

[DaveW555]

Crank Sensor will also give this problem take your pick which you do first.