1st Generation S-series (1983-1994) Tech Discuss 1st generation S-series (1983-1994) general tech topics here.

93 S10 Blazer W Fuel Pressure Problem

  #1  
Old 03-22-2015, 07:57 PM
Jesse31's Avatar
New Member
Thread Starter
Join Date: Jul 2010
Posts: 4
Jesse31 is on a distinguished road
Exclamation 93 S10 Blazer W Fuel Pressure Problem

July 2010…Hard start especially when cold…looked at CPI spider and it was leaking and the lines were leaking…replaced CPI spider/regulator and Nut Kit (lines)…ran great until July 2013…no start at all…fuel pump failure…replaced with Carter pump…ran good until recently…began troubleshooting…installed new fuel filter…regulated pressure at 45 psi…replaced fuel pump with Delphi unit…checked Fuel Pump Maximum Output Pressure…82 lbs…regulated pressure now at 48 psi (key on engine off)…after 5 minutes leaks down to 35 psi...looking at the picture, I am thinking it must be the fuel pressure regulator?...(damaged by ethanol?)...lots of washing going on around it...I need expert advice...anyone have thoughts on this?...can the regulator be replaced independent of the whole CPI spider?
 
Attached Thumbnails 93 S10 Blazer W Fuel Pressure Problem-img_0689.jpg  
  #2  
Old 03-22-2015, 08:19 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

On your '93:


First test. Checking pressure and leakdown at the fuel filter outlet: With the pump activated, pressure should be ~70psi to ~100psi and it must remain above 50psi for at least 10 minutes after the pump shuts off. If both of these readings are within spec, The fuel pump is OK.


Second test. Checking regulated fuel pressure at the service port near the distributor: Key on, engine off, fuel pump activated, pressure must be 55-61 psi, and it must remain above 50psi for at least 10 minutes after the pump shuts off.


If the first test is OK, and regulated pressure is low, the regulator needs replacement. If the leakdown is excessive, with no visible leaks, further testing is necessary to determine what is leaking.


The regulator can be serviced separately.
 
  #3  
Old 04-05-2015, 09:22 PM
Jesse31's Avatar
New Member
Thread Starter
Join Date: Jul 2010
Posts: 4
Jesse31 is on a distinguished road
Default

Thanks for the help Captain Hook!...Replaced the regulator and that was it...the regulator was only 4 1/2 years old...ethanol damaging them?
 
  #4  
Old 04-06-2015, 03:23 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

Ethanol is good if you have water in your fuel. Other than that, it's best to avoid it if possible. Thanks for posting back.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
jcannon
2nd Generation S-series (1995-2005) Tech
11
04-02-2013 10:37 AM
chevyracingfan23
2nd Generation S-series (1995-2005) Tech
14
06-19-2012 02:32 PM
jimbob533
Engine & Transmission
0
11-14-2011 06:02 PM
hobbs2
1st Generation S-series (1983-1994) Tech
3
02-11-2010 01:28 PM
Spartan66
2nd Generation S-series (1995-2005) Tech
6
07-11-2008 02:34 PM


Thread Tools
Search this Thread
Quick Reply: 93 S10 Blazer W Fuel Pressure Problem



All times are GMT -5. The time now is 11:23 PM.