Pressurize fuel system to test for fuel leaks

Brent · 02-23-2008, 11:16 AM

If you have an aftermarket fuel rail, which normally includes a FPR and gauge, to pressurize the system to check for fuel leaks you can simply put the key in the ignition and turn the key to the "on" position. This will run the fuel pump for 2 seconds allowing fuel pressure to come up. You can then simply look at your gauge and see if it is holding pressure. This works best if you have a helper doing this so you can look to see if you see any fuel coming out. If it is a slight leak, you'll want to put your finger under the fittings and see if they are wet. I *believe* the pressure should be around 36-38psi if I remember correctly. You can also go to the black "diagnostic" box and take a piece of wire. touch the pin labeled f/p with one end and the other to the ground(grnd). I have recently had several fuel leak issues that I have sorted out and have been working on a fuel system troubleshooting how to... should be finished and posted with pictures and video's within a day or two.

Checking to see if you are getting fuel: You can check to see if your injectors are firing by testing a few things. First thing, verify that your injectors are opening and closing. To do this, take a set of small jumper clips. Place one on each prong. Put the other ends of the clips, place one on a power source. You will then take the last clip and touch it to a ground anywhere in the engine bay. When you do this, you should here a click. This verifies that your injectors are opening and closing. Make sure you do this to both primary injectors.
Next, verify that you are getting a signal from the ECU. In order to do this, you can purchase a $20 node light set from Advanced Auto Parts. It's in a red plastic box. The set will come with several node lights. The bosch one will fit into the stock FD or the bosch injector clips. Simply plug it into the injector clip and have someone turn the car over. If the light flashes in pulses, your injector connectors are working as they should. If they do not flash, you have a problem.
If you are still not sure you are getting fuel into the engine, you can check the spark plugs to see if they have fuel on them or disconnect the primary fuel rail(after relieving fuel presure) and lift it out. Once you lift it out, physically look at the bottom of the injectors to see if they are wet.

dudemaaan · 03-30-2008, 12:53 AM

good writeup. my name is brent too. i think you posted this over on the other forum as well.

02-23-2008, 11:16 AM	#1
Brent Sua Sponte Join Date: Feb 2008 Location: Killeen, TX iTrader: (4) Posts: 839 Rep Power: 17	Pressurize fuel system to test for fuel leaks If you have an aftermarket fuel rail, which normally includes a FPR and gauge, to pressurize the system to check for fuel leaks you can simply put the key in the ignition and turn the key to the "on" position. This will run the fuel pump for 2 seconds allowing fuel pressure to come up. You can then simply look at your gauge and see if it is holding pressure. This works best if you have a helper doing this so you can look to see if you see any fuel coming out. If it is a slight leak, you'll want to put your finger under the fittings and see if they are wet. I believe the pressure should be around 36-38psi if I remember correctly. You can also go to the black "diagnostic" box and take a piece of wire. touch the pin labeled f/p with one end and the other to the ground(grnd). I have recently had several fuel leak issues that I have sorted out and have been working on a fuel system troubleshooting how to... should be finished and posted with pictures and video's within a day or two. Checking to see if you are getting fuel: You can check to see if your injectors are firing by testing a few things. First thing, verify that your injectors are opening and closing. To do this, take a set of small jumper clips. Place one on each prong. Put the other ends of the clips, place one on a power source. You will then take the last clip and touch it to a ground anywhere in the engine bay. When you do this, you should here a click. This verifies that your injectors are opening and closing. Make sure you do this to both primary injectors. Next, verify that you are getting a signal from the ECU. In order to do this, you can purchase a $20 node light set from Advanced Auto Parts. It's in a red plastic box. The set will come with several node lights. The bosch one will fit into the stock FD or the bosch injector clips. Simply plug it into the injector clip and have someone turn the car over. If the light flashes in pulses, your injector connectors are working as they should. If they do not flash, you have a problem. If you are still not sure you are getting fuel into the engine, you can check the spark plugs to see if they have fuel on them or disconnect the primary fuel rail(after relieving fuel presure) and lift it out. Once you lift it out, physically look at the bottom of the injectors to see if they are wet. __________________ Road Atlanta August 2011 NASA TT 1:33 http://www.youtube.com/watch?v=IFY00PAK_Ps Traqmate's video of my car from the 2011 UTCC at VIR http://www.youtube.com/watch?v=2Zcn6...layer_embedded Video of Yellow LS1 FD at NASA TT at VIR http://www.youtube.com/watch?v=e6k0lJkcwrM Last edited by Brent; 02-24-2008 at 12:41 PM..

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03-30-2008, 12:53 AM	#2
dudemaaan Rotary Fanatic Join Date: Mar 2008 Location: Brenham, TX iTrader: (4) Posts: 335 Rep Power: 17	good writeup. my name is brent too. i think you posted this over on the other forum as well.