Does my fuel pressure look right?
12-02-2007, 09:58 PM
#1
5th Gear Member
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Join Date: Jan 2006
Posts: 2,504
Does my fuel pressure look right?
hey guys, i'm trying to track down the cause of my hesitation, power loss and all around crappy running car. so i put a gauge on the fuel rail and i'm getting 26-28 psi @ idle and around 38 psi when i disconnect the vacuum line.
does this seem rignt? i don't know what the specs are but isn't it supposed to be higher?
does this seem rignt? i don't know what the specs are but isn't it supposed to be higher?
12-02-2007, 10:07 PM
#4
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Join Date: May 2006
Location: Ohio
Posts: 6,448
RE: Does my fuel pressure look right?
I'll try to find out what the pressure is supposed to be when I get off here in a few min and get to my computer. But I think it should be 30-40 at idle. What vacum line did you disconnect. You have an 03 so you dont have a regulator under the hood. Don't disconnect the vacum form the fps.
12-02-2007, 10:23 PM
#5
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Join Date: Jan 2006
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RE: Does my fuel pressure look right?
it was acting up before the new coils, and i also have new o2 sensors......... and a new fuel filter, plugs and MAF but it still runs bad [:@]
yea i pulled the line off the fps to see if the pressure would rise
What vacum line did you disconnect. You have an 03 so you dont have a regulator under the hood. Don't disconnect the vacum form the fps.
12-03-2007, 08:29 PM
#7
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Join Date: May 2006
Location: Ohio
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RE: Does my fuel pressure look right?
Fuel pressure should be 40 psi. Since you have an 03 with 21lbs injectors it will actualy be 20lbs at 43.1 psi it will spray 21lbs but 40 is recommended. If your running 26-28psi there is something wrong
Returnless systems are very sensitive to fuel pressure, and if pressure is more than a few pounds out of specifications, it may be enough to cause a driveability or emissions problem. Fuel pressure checks on returnless systems can be done in the usual way by attaching a gauge to the service valve fitting on the fuel supply rail, or you can hook up a scan tool and read the pressure value via the pressure sensor. Using a fuel pressure gauge to cross-check the accuracy of the electronic reading is a good way to check for a fuel pressure sensor that is out of calibration.
Returnless systems are very sensitive to fuel pressure, and if pressure is more than a few pounds out of specifications, it may be enough to cause a driveability or emissions problem. Fuel pressure checks on returnless systems can be done in the usual way by attaching a gauge to the service valve fitting on the fuel supply rail, or you can hook up a scan tool and read the pressure value via the pressure sensor. Using a fuel pressure gauge to cross-check the accuracy of the electronic reading is a good way to check for a fuel pressure sensor that is out of calibration.