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1973 S MFI problem

Fuel System

Vehicle Information: Model: 911S Targa; Year: 1973; Body Type: Targa; Engine (type, size, modifications): 2.4, SSI, Carrera tensioners; Total Mileage: Since motor/fuel syst. rebuild - 25k, since total body resto - 100 miles;

Getting my restoration project back on the road finally!!!Engine starts ok when cold, and once warmed up, runsvery nicely without any mid-range surge. Idle is good,and CO is at 3.5% at idle and 3-4% at 2500-3500 rpm (no-load),so the rack seems to be adjusted correctly.I know the CO is low (more like factory spec),but the car does run nice at these settings.Ignition timing is also on correct.When the car is warmed up, the engine will start ifyou try immidiatly, but if you let it sit for more thana minute, it will not re-start. Not even a hint at fireing. The cold-startinjectors are not squirting (as they shouldn't) atthis point. I don't really know if I'm gettingtoo much or too little fuel at this point.I tried all throttle positions.I rigged up a push-button switch to the cold-startsolenoid, and while cranking hot, gave it a fewsquirts, with no change.The car will re-start fine in about 2-3 hours.I removed the injectors to soak them in Ventil Sauberovernight, and when disconnecting the fuel lines fromthe injectors, it seamed like the lines were dry (atthis point the car had sat for 4 hours). Is there somesort of check valve in the MFI pump to keep the linesfilled, or is the pump expected to re-fill the linesonce you crank?I'm not quite sure where to go from here, any thoughts or advice??

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