Intermittently hard start/extended cranking

2003 CHEVROLET SILVERADO
184,000 MILES • 6.0L • V8 • 4WD • AUTOMATIC
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RYAN REED
  • MEMBER
  • 1 POST
Intermittently extended crank but starts every time. Replaced fuel pump, fuel filter, fuel pressure regulator. Cleaned and new o-rings on injectors. TPS replaced. No check engine light. Beginning to think sensor? Plugs and wires done 5,000 miles ago. New air filter and MAF cleaned. All this has been done since symptoms have started. No improvement. What am I missing?
May 24, 2021 at 9:28 AM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
The first thing I need you to check is a ground wire for the ignition coils. All of the coils share a common ground and they are known to go bad.

When standing at the front of your truck, on the right side of the engine (near the front of the engine) and low on the block is where the ground is located. It will be a black wire. Check its condition where it connects. The connector ring that the bolt runs through breaks down causing a weak or no spark condition.

Once you find the ground, move it around to make sure the wire is still firmly attached to the connector. Remove the bolt, clean all corrosion from the connector, bolt, and engine block at that point.

If that is in good condition and there is no evidence of damage, here is a video that explains how to test fuel pressure. I realize the pump is new, but confirm that it is working properly.

https://youtu.be/peh7-pFycyc


Let me know if that helps or if you have other questions.

Take care,

Joe
May 25, 2021 at 2:07 PM
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