Just recently, at 78K miles, the engine requires 3 crank cycles of 3 to 4 seconds for the first morning start. Any other time, starts and runs perfectly. Cycling the key 3 times for 3 seconds without starting does not help. Fuel pressure is steady at 60psi at idle and under load. 3000 miles before the hard starting problem surfaced, a new fuel filter and spark plugs were installed (maintenance items). The factory plugs looked good with a measured 0.070" gap (0.060" spec) and the engine was running well. The throttle body was cleaned and a new air filter was installed. No diagnostic codes. I suspect that fuel is leaking back to the tank overnight. Fuel pressure regulator the culprit? Can a dirty crank position sensor magnet cause this problem? Thanks for any suggestions. Bob
Hard Starting at 60°F on 2000 Chevrolet Silverado 1500
by Bob - The Maintenance Guy in East Peoria, IL on October 30, 2010
ANSWER by Superbob , October 31, 2010
Did you check what the fuel pressureis when you turn the key first thihg in the morning when you have the problem? I'd be more suspicious of the fuel pressure regulator and internal check valve than the crank position sensor magnet but you could test the waveform and signal voltage and see if it's not good when cold.