2L duratec cuts out upon hot restart

[juliethotel]

2007 S max with a 2L Duratec engine.

Car runs perfectly. When I restart it when it's hot it starts but then cuts out right away. The car can run hot for ages but only starts messing around upon a restart.

There's no eml on. The fact it runs so well rules out basic stuff like plugs and coil packs (you'd think)

EGR?

Where do I start?

[E-bmw]

How long does it need to be off before restarting is an issue?

[juliethotel]

[quote=E-bmw]How long does it need to be off before restarting is an issue?[/quote

Yeah this is the other thing, it will run fine if restarted straight away but leaving it off for longer than a couple of mins and it starts screwing around.

[finlo]

juliethotel said:

E-bmw said:

How long does it need to be off before restarting is an issue?[/quote

Yeah this is the other thing, it will run fine if restarted straight away but leaving it off for longer than a couple of mins and it starts screwing around.

Heat soak evaporating the fuel in the float bowl's of the SU carb!

[E-bmw]

I would say either that of fuel fall back.

When you start it cold rather than warm do you allow the fuel pump to prime the system first?

[LeftLake]

I have a MK2 focus with this engine, and have had a similar problem (pretty much since new). Definitely a fuel issue on starting when the engine is warm, and on hot sunny days. Usually find giving it a bit of gas when turning over (and you hear it starting to struggle) does the trick. On some occasions it has taken a few attempts to restart though!

[juliethotel]

E-bmw said:

I would say either that of fuel fall back.

When you start it cold rather than warm do you allow the fuel pump to prime the system first?

Yes I always wait 2/3 seconds until cranking it whether it be hot or cold.

[E-bmw]

juliethotel said:

E-bmw said:

I would say either that of fuel fall back.

When you start it cold rather than warm do you allow the fuel pump to prime the system first?

Yes I always wait 2/3 seconds until cranking it whether it be hot or cold.

OK, that would likely rule both out assuming it has the opportunity to fully prime.

[john2443]

I had a similar thing on a Fiat which turned out to be crankshaft sensor. I have no idea if this is relevant to your car though!

[meb90]

LeftLake said:

I have a MK2 focus with this engine, and have had a similar problem (pretty much since new). Definitely a fuel issue on starting when the engine is warm, and on hot sunny days. Usually find giving it a bit of gas when turning over (and you hear it starting to struggle) does the trick. On some occasions it has taken a few attempts to restart though!

Ha! I have a Mk6 Fiesta ST, so the same engine. Always starts first time easily when cold, but if I turn it off hot and leave it for any length of time it needs a healthy dose of throttle to get it started!

I haven't got to the bottom of it yet as I have a work around, but I do have a crankshaft position sensor in the garage awaiting fitting in case that is it.