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FMU / Pressure question

  • Thread starter Thread starter Steve 9450
  • Start date Start date Aug 8, 2005
S

Steve 9450

Founding Member
Oct 30, 1998
133
0
16
Minooka,IL
Aug 8, 2005
#1
  • Aug 8, 2005
  • #1
Help, looking for advice. For some reason the fuel pressure reading is now around 50 psi. The car was always around 40-42. I have the electric fuel gauge inside and the air/fuel gauge indicates the car car is running rich at idle. Is there something simple I can check. Any help would be great.. Thanks
 

CManT1914

New Member
Feb 5, 2004
3,172
2
0
Killeen, Texas
Aug 8, 2005
#2
  • Aug 8, 2005
  • #2
Did the fuel pressure jump up after you installed the FMU? If you have an AFPR, then you can just drop the fuel pressure in about 15 seconds.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Aug 8, 2005
#3
  • Aug 8, 2005
  • #3
Is this gauge a wide band or one with colored lights?

Later
Grady
 
S

Steve 9450

Founding Member
Oct 30, 1998
133
0
16
Minooka,IL
Aug 9, 2005
#4
  • Aug 9, 2005
  • #4
The gauge is the one with the colored lights. The FMU was installed appox. 5 yrs. ago. The pressure just jumped this weekend. The idle also seems to have gone high also. it used to idle around 820-920 rpms now it fights to get below 1500 rpms. Can those fmu go bad? The car just turned 28000 miles on it. Thanks for any input......Steve
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Aug 9, 2005
#5
  • Aug 9, 2005
  • #5
Steve 9450 said:
The gauge is the one with the colored lights. The FMU was installed appox. 5 yrs. ago. The pressure just jumped this weekend. The idle also seems to have gone high also. it used to idle around 820-920 rpms now it fights to get below 1500 rpms. Can those fmu go bad? The car just turned 28000 miles on it. Thanks for any input......Steve
Click to expand...

Steve

Its good that you gave the additional info

Since everything has been the same for a while, it seems that something is not working correctly which is causing the new symptoms.

I'd check the easy stuff first like:
clean the maf wires
clean the idle speed controller or what ever you choose to call it, lol
check for v leaks
check all connectors

Later
Grady
 
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