CHEVROLET VAN ENGINE HARD TO START

1978 Chevrolet G20 Van, 5.7liter, 4bbl, 135,000 Miles: I Drive This Van On The Weekends Only And After It Has Sat For A Week It Takes Me...

When You Try To Start The Van Sometimes It Does Not Start, When You Let Off The Key It Starts, Once It Is Running It Shuts Off I Also...

I Have A 1999 Chevy 3500 Van With A 5.7l That's Been Not Wanting To Start Very Well As Of This Week. It Will Start After The 3rd Or 4th Time...