[Diy_efi] Warm Start Problem

[Bill Washington]

Mike,
    To me this sounds reminiscent of a heat soak/fuel vaporisation problem.
I would look at fuel distribution manifold temp, and also your low and 
high pressure pumps - if your high volume/low pressure pump (often in 
tank) has died the high pressure pump may not be able to supply enough 
fuel flow to clear a vapour lock in the manifold.
I had a problem where the engine would cut out on a hot day on the 
highway if the fuel tank was below 1/3 full - in the city, no problems, 
more fuel in the tank, no problems - the entire commutator on the low 
pressure pump had worn away! - I replaced the pump, problem solved!

Good luck
Bill
>
> Subject:
> [Diy_efi] Warm start problem...
> From:
> Mike Frels <mfrels at ix.netcom.com>
> Date:
> Wed, 11 Jul 2007 18:28:14 -0600 (GMT-06:00)
> To:
> diy_efi at diy-efi.org, gmecm at diy-efi.org
>
> To:
> diy_efi at diy-efi.org, gmecm at diy-efi.org
> CC:
>
>
> I am trying to diagnose a hot or warm start problem. I've got a gm TPI 350 running $8D for a 305 that has been modded to work with my setup. Morning starts she fires right up. Hot starts if she's only been sitting for less than 10-15 minutes also fine. A restart between 15 minutes to 5 hours sitting takes some cranking. Looking through my tables I've got various Start Up Enrichment and Crank Fuel Pulse Width settings that I am thinking I need to adjust. Can someone enlighten me on what the differences between Start Up Enrichment and Crank Fuel Pulse Width? BTW I have acquired this summer time problem since I switched to LS1 injectors last year.
>
> Mike
>   
>