1998 Chevrolet Silverado backfires, difficult start

1998 CHEVROLET SILVERADO
200 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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GOODSTUFF21
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  • 1 POST
Will a fuel pump from a small GMC pickup cause the silverado to backfire. Ithassle. Idles slow, must turn key 2xs to start, backfires going down hill.
Mar 12, 2015 at 6:03 AM
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JDL
  • ✓Experienced Mechanic
  • 16,098 POSTS
Use a fuel pressure gage and check proper fuel proper. Also, check fuel volumn. Use the proper fuel pump for the vehicle.

Usually the fuel pressure gage has a pressure bleed off valve. engine idling, clear plastic tube, aim into container, press the button, if the fuel system is strong, the idle shouldn't miss a beat.

Your auto store may loan out a fuel pressure gage, some of the national brand auto store will loan. You may have to put up deposit, but, you get it back when tool is returned.
Mar 12, 2015 at 7:08 AM
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JDL
  • ✓Experienced Mechanic
  • 16,098 POSTS
Just to add, if you have the spider fuel system, fuel pressure on start-up can be critical. Key on engine off, 60--66 psi.

The spider fuel system is noted for problems.

How long since a tune-up? Any applicable trouble codes? Some of the national brand auto stores will check codes for free.
Mar 12, 2015 at 7:17 AM
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