1998 Chevy S-10 fuel pressure

1998 CHEVROLET S-10
Avatar
MIKE TAPP
  • MEMBER
  • 1 POST
Engine Mechanical problem
1998 Chevy S-10 4 cyl Two Wheel Drive Manual 158k miles

I have checked the fuel pressure with gauge. with the key turned to on position it climes to 40 psi then dropes back to 0 psi. with truck running fuel pressure stays at 36 psi. should the pressure ramp up to 40 psi and drop all the whey to 0 psi or should it hold a slight pressure while the key is on?
Feb 17, 2010 at 2:35 PM
Advertisement
Avatar
JDL
  • CAR REPAIR CONTRIBUTOR
  • 16,098 POSTS
Welcome to the forum. When you build pressure and turn off, it shouldn't drop more than 5 psi in 10 minutes, according to my info. If it drops like a rock, pull the vacuum line off the pressure regulator, see if there is any gas in there, If so, replace the regulator. If that checks out, build pressure, turn off, see if you can pinch the supply line somewhere it doesn't crush anything, if the drop stabilizes, suspect the fuel pump is letting the pressure drain. If not injector/s may be leaking?
Feb 17, 2010 at 3:00 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.