'96 E320 Hard Starting Problem

[dasbus]

We are having a hard starting problem with our '96 E320. I starts OK when it's cold, but when it's warm we have to crank on it for a while, probably 20-30 seconds before it will start. If I re-start it within a couple minutes it will fire right up, longer then that I'm cranking on it again. There is plenty of power and the fuel mileage is fine. The Mass Air Sensor was replaced a few weeks ago due to stalling incidents, the problem started before that and seems to be unrelated since it is continuing. The battery is about 6 months old and I replaced the plugs last week. It always starts eventually, but it is kind of annoying that it doesn't just fire right up like it used to. Anyone else had this problem?

Thanks,
Doug

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