Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

test fuel pressure with vacuum pump?


bledsoe's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:15 AM   #1  
bledsoe
test fuel pressure with vacuum pump?

Guys, I don't have a fuel pressure gauge, but I have a vacuum pump. Can I use that to test fuel pressure on a fuel injected engine? I've read that there's generally a schrader valve somewhere inline between the fuel rail and the tank itself, so can I hook it up somewhere in between there? Could you quickly walk me through the steps of doing this test with either the pump or fuel pressure gauge. Thanks. my vehicle is a '96 jeep cherokee, 4.0.

 
Sponsored Links
Joe_F's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:20 AM   #2  
Joe_F
No way .

Go to Autozone and pick up one from their tool rental program. They don't charge as I recall.

 
bledsoe's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:26 AM   #3  
bledsoe
Ok, could you quickly walk me through the steps to perform the test? Thanks

 
Joe_F's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:31 AM   #4  
Joe_F
You should pick up a repair manual as each vehicle differs.

The kit should also have the testing instructions, so follow them to the T.

Why are you checking the fuel pressure?

 
bledsoe's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:49 AM   #5  
bledsoe
I actually don't need to check it, but was just wondering how "in general" to perform this test, just for the sake of knowing how to do it. I don't need specifics to my vehicle, just wondering how it's done. I'm guessing you would relieve the pressure in the system somehow(opening gas cap?), then turn on fuel pump(by turning key to "on" position), and watch the gauge wherever you hook it up.... Am I close? Do all vehicles have a valve that you can hook up a fuel pressure gauge to?

Again, I was just wondering in general. just keeping busy at work...

 
Joe_F's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:51 AM   #6  
Joe_F
You check cranking pressure, regulated pressure (running engine) and bleed down.

Most have the schrader valve. Not all do.

You want to look at the way the manfacturer wants you to test the pump, again they all vary in what they want . But yes, you are on the right track.

 
bledsoe's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:58 AM   #7  
bledsoe
Thanks. Since you mention it, my '96 cherokee with 90K miles does actually take a few seconds of cranking before it actually turns over. Because of this, I was actually thinking of checking the fuel pressure, but since it isn't a problem yet I guess I'll hold off for now. Thanks dude

 
Joe_F's Avatar
Visiting Guest

Posts: n/a

01-31-02, 09:59 AM   #8  
Joe_F
Those always had a bit of an extended crank from what I recall.

Sure, no problem.

 
bledsoe's Avatar
Visiting Guest

Posts: n/a

01-31-02, 12:03 PM   #9  
bledsoe
Joe, do you know if this vehicle's trouble codes can be retrieved with an OBDII scanner. If not, do you know how? '96 Cherokee

 
Joe_F's Avatar
Visiting Guest

Posts: n/a

01-31-02, 12:53 PM   #10  
Joe_F
Yes, on this vehicle you need an OBDII machine to retrieve your codes.

Again, Autozone for one place, rents them.

 
Search this Thread