2nd Generation S-series (1995-2005) Tech Discuss 2nd generation S-series (1995-2005) general tech topics here.

Low voltage at fuel pump

Old Jun 11, 2012 | 08:54 PM
  #1  
sick s10 blazer's Avatar
Thread Starter
|
New Member
Joined: Jun 2012
Posts: 3
sick s10 blazer is on a distinguished road
Default Low voltage at fuel pump

I have a 95 S10, Vortec v6,4.3,4door, 4 wheel drive. It has low fuel pressure. With a brand new Bosch pump in. So I ck voltage at pump. Its only 8.6 volts. Everywhere else I ck I get 12. What am I missing????
 
Old Jun 11, 2012 | 10:14 PM
  #2  
Captain Hook's Avatar
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

Just a friendly FYI: aftermarket fuel pumps are NOT recommended on 4.3L Vortec engines, AC Delco or Delphi only, unless you like changing the pump

When the ignition is turned to the RUN position, (engine off) the fuel pump is only energized for 2 seconds, so you must check voltage during that 2 second time frame. Have you checked resistance from the fuel pump module electrical connector to ground? Must be less than 5 ohms. Which style connector is on the pump module?



Name:  HarnessConnectors.jpg
Views: 10374
Size:  13.8 KB
 
Old Jun 12, 2012 | 07:06 PM
  #3  
sick s10 blazer's Avatar
Thread Starter
|
New Member
Joined: Jun 2012
Posts: 3
sick s10 blazer is on a distinguished road
Default

Originally Posted by Captain Hook
Just a friendly FYI: aftermarket fuel pumps are NOT recommended on 4.3L Vortec engines, AC Delco or Delphi only, unless you like changing the pump

When the ignition is turned to the RUN position, (engine off) the fuel pump is only energized for 2 seconds, so you must check voltage during that 2 second time frame. Have you checked resistance from the fuel pump module electrical connector to ground? Must be less than 5 ohms. Which style connector is on the pump mo

My connector is only a 3 wire. At key turn on I do get the 12+ v. But resistance is around 30.
 
Old Jun 12, 2012 | 07:33 PM
  #4  
Captain Hook's Avatar
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

My bad, 1995, sorry. 30 ohms is too much resistance in the ground circuit, (probably what toasted the old pump). Solder on a 14 gauge piece of wire at the module connector and run it to a good, clean, body ground.
 
Old Jun 13, 2012 | 10:03 PM
  #5  
sick s10 blazer's Avatar
Thread Starter
|
New Member
Joined: Jun 2012
Posts: 3
sick s10 blazer is on a distinguished road
Default

Originally Posted by Captain Hook
My bad, 1995, sorry. 30 ohms is too much resistance in the ground circuit, (probably what toasted the old pump). Solder on a 14 gauge piece of wire at the module connector and run it to a good, clean, body ground.
Capt. Hook. Thank you very much. Did that tonite. 1ohm. Hopfully this all works out. Darn tired of droppin that tank.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
RJWolfe
2nd Generation S-series (1995-2005) Tech
8
Feb 17, 2019 07:32 PM
NV4x4BLazer00
2nd Generation S-series (1995-2005) Tech
10
Mar 10, 2012 08:57 PM
2001Blue
Lighting & Electrical
13
Dec 31, 2010 12:16 PM
cjp5
2nd Generation S-series (1995-2005) Tech
0
Sep 15, 2010 07:51 AM
c4gibson
2nd Generation S-series (1995-2005) Tech
7
Apr 4, 2008 10:49 AM


Thread Tools
Search this Thread

All times are GMT -5. The time now is 11:34 AM.