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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 15201
Experience:  GM Grand Master Technician 2007. 14 years experience.
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1998 GMC 5.7 STARTS ON FIRST TIME WHEN COLD START THEN HARD

Customer Question

1998 GMC 5.7 STARTS ON FIRST TIME WHEN COLD START THEN HARD TO START WHEN HOT
JA: Will the headlights turn on? Is the battery fully charged?
Customer: YES
JA: What is the model of your '98 Chevy?
Customer: 1500
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: TEMP SENSOR FUEL PUMP AND FILTER CRANK SENSOR CAP AND BUTTON
JA: Anything else you think the mechanic should know?
Customer: STARTER CHANGE
Submitted: 8 months ago.
Category: Chevy
Expert:  AMEDEE replied 8 months ago.

Hello and welcome! What happens when the engine is hot? Does it NOT crank over at all or does it crank over slow when this happens?

Customer: replied 8 months ago.
cranks fine wont start till 5 or 6 cranks
Expert:  AMEDEE replied 8 months ago.

So it is a hard start condition. What has been replaced for this already? Have you checked the fuel pressure when this happens?

Customer: replied 8 months ago.
replaced fuel pump and filter dris.cap and button temp.sensor crank senor fuel relay
Expert:  AMEDEE replied 8 months ago.

Thanks for that information. So what is the fuel pressure at when this hard start condition occurs?

Customer: replied 8 months ago.
60 psi then cut off gose to 40 turn key 4 or 5 times it starts
Expert:  AMEDEE replied 8 months ago.

The fuel pressure needs to be at about 60 psi for the engine to start properly. I bet this is the problem.

Customer: replied 8 months ago.
right at 60 starts fine but when cold starts first time when hot the problem starts
Expert:  AMEDEE replied 8 months ago.

Your fuel pressure regulator or fuel injectors might be leaking fuel into the engine causing the low fuel pressure issue.

Customer: replied 8 months ago.
truck runs good no skips or hold back
Expert:  AMEDEE replied 8 months ago.

If the fuel pressure is at 40 psi at anytime, this needs to be addressed.

Customer: replied 8 months ago.
no help thanks for your time
Expert:  AMEDEE replied 8 months ago.

Good luck

Customer: replied 8 months ago.
NO THANKS