Ls2 Hot start Problem

[matt]

Hi Guys, I have a Cobra kit with a 2005 Ls2 with E40 ECU and 24t Reluctor wheel. It runs a std 2005 Pontiac GTO tune file with no evap... Starts fine from cold first time every time. When the engine has warmed up it runs fine with no problems. All water and oil temperatures remain stable at normal operating temperatures. When I stop the car, turn the engine off and the car is left for a while, say 5-10 mins or even up to an hour or so. When I attempt to re-start the engine it cranks over and over and over but will not fire up !!!! The fuel pump kicks in ok, the battery is good and there are no fault codes present.....It does eventually fire up and sometimes slugishly.....Or if I stop cranking wait a few seconds and then crank again it satarts almost imediately.... It had a new Crank Sensor last year after it would not start at all after winter storage....So I dont think this is the issue....This just happens when the engine is warm... Does anyone have any experience of this??? If so did you get a fix ??

[c.u]

Is the motor stock?

[matt]

Hi, Yes completley standard engine all round. No mods.. :-)

[joecar]

What is pressure at fuel rail...?

Is your FPR manifold-referenced or not...?

[matt]

What is pressure at fuel rail...?

Is your FPR manifold-referenced or not...?

Hi, The fuel pressure at the rail after starting is 60 PSI. When cranking from hot it only makes 20 PSI and then as you keep cranking it slowley rises to 60 psi and then starts....Sorry I do not quite know what you mean by FPR manifold reference?

[krisr]

Does your fuel pressure regulator connect to manifold vacuum or not is what he meant.

[matt]

Does your fuel pressure regulator connect to manifold vacuum or not is what he meant. Hi Krisr, Ahh, I understand....Er No it is not connected. Just blocked off.

[joecar]

If rail pressure is not at full running pressure (60 psi in your case) right from the start, then there is your hot-start problem.