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is my Fuel pump bad?

  • Thread starter Thread starter Raginstang
  • Start date Start date Feb 22, 2006
R

Raginstang

New Member
Sep 28, 2003
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SANTA CRUZ CA
Feb 22, 2006
#1
  • Feb 22, 2006
  • #1
Okay, so now that ive pretty much decided to get a new pump.. I think my old one may be taking a dive.. my car was running very poor at low rpms.. and off idle.. also was running hot. now all of the sudden it wont start.. I do have spark. I can hear the fuel pump coming on.. my in car Autometer fuel pressure guage only goes to 20psi then falls to zero when I just turn the key to prime it. I disconnected the fuel line before the regulater and stuck a cup under it and measure it with a measuring cup.. heres what I found

Prime-(just turned key to start positon)= less than 1/4 of a cup

5 Second Start-(I cranked the motor for 5 seconds)= Almost 1/2 a cup

don't know if this helps.. but is that enough fuel? I confused cause I can hear the pump coming on.. just maybe not enough pressure? or volume? could also of been causing the problems? thanks..
 
P

Propony

New Member
Jan 16, 2004
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Va
Feb 22, 2006
#2
  • Feb 22, 2006
  • #2
replace fuel filter first...
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Feb 22, 2006
#3
  • Feb 22, 2006
  • #3
If you turn the key to run (to prime the pump) several times before cranking (to build pressure), what happens? Does pressure go up to 30+ PSI?

Anything under 30 PSI while a car is running is not acceptable.


Good luck.
 
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