hot starting issue advice please

[gmf_uk]

when my engine is cold it starts fine every time, but once hot the first time i try to start it it turns over fine but wont fire, then when i turn the key the second time it fires straight away. this happens 90% of the time when the engine is hot. Where should i start looking, Thanks

[Rtaylor2208]

1st thing to do is test the blue temp sensor at the thermostat housing / ECU. Search the wiki for blue sensor and a full guide is detailed on how to do it.

[gmf_uk]

will do thankyou