'97 E320: Delayed hot start.

I'm looking for opinions about my diagnosis.
I've owned a '97 E320 (24 valve straight six) since new. After about 15K miles it began to have a delayed hot start, specifically, after being
driven for at least 3 miles and parked for a half hour to 4 hours it cranks but won't start until I step on the gas to open the throttle. Then it starts with a roar and initially acts like it was "flooded" as we used to say with carburated engines.
The car has now gone 33K miles and the problem is consistent. The engine is otherwise very responsive, smooth, good power and good fuel economy. The spark plugs were changed at 30K miles and I checked the fuel system pressure regulator - it was fine, no fuel leak into the intake manifold.
My diagnosis is that the injectors are leaking fuel into the intake ports and the engine is, in fact, being "flooded" after shut down. A confirming symptom is that when I changed the spark plugs #6 spark plug was wet with fuel; the others were normal. However, my diagnosis is made with no knowledge of how the idle speed is controlled and what happens there when the engine is cranked: i.e. does the idle speed controller have a "start" position? I don't know and the Bosch fuel injection book doesn't discuss hot starting.
So I'd appreciate your opinions and ideas.
Thanks,
Tom
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I would say you are on the right track... leaky fuel injector or any other fuel injection device that lost pressure. #6 injector would be the culprit since you got wet fuel saturated spark plug.
Don't doubt yourself there TG... you practically answered your own question. The other possibilty is fuel checkvalve at the fuel pump leaking pressure.
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Tom -
I think Tiger's got it pretty well caged - - if it ain't an injector, it pretty much has to be that pesky check valve. I just had new injectors all around less than a year ago due to California smog problems, but still have a slight hot start issue - not real bad, but it sure doesn't start at the first turn of the key like Tiger's. I'm about to attack the check valve, but would appreciate hearing back on here whatever your resolution turns out to be. Do keep us posted, won't you?
Jerry Wolfram '78 450 SL - 212K miles
Tiger wrote:

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Thanks for your vote of confidence, Tiger.
Question: If the fuel pump's check valve were leaking wouldn't the cold start also be delayed? (cold start is perfect)
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You are absolutely correct too... would be a slight delay.
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