checking Fuel Pressure - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

nrmskate · 01-23-2009, 12:02 PM

Well, the problems I have been having lateley leave me and my mechanic to believe that my problem could be fuel related. He asked me to do a fuel pressure test to check it out.

So, I just wanna make sure im doing it right.

-Unplug Fuel Pump Relay
-Open gas cap
-T clamp with press gauge
-Install fuse back in and shut gas cap
-Ignition "on" and read the gauge?

I think it's right, just wanna make sure everything looks good before I possibly fuck something up.

Thanks.

Otto347 · 01-23-2009, 12:37 PM

Sounds right, it should build up the correct pressure (or not) then go from there.

I usually just get a towel and wrap it around the fuel line where im taking it apart. Pop it off and the fuel goes on the towel but guess the extra caution doesnt hurt.

sbc · 01-23-2009, 12:39 PM

With the car running pull the fuel pump fuse and let the engine die out. Open the gas cap to relieve the pressure. T your gauge into the regulated fuel line. Put the fuse back in and then start it up.

alkemyst · 01-23-2009, 12:42 PM

Quote:

Originally Posted by sbc

With the car running pull the fuel pump fuse and let the engine die out. Open the gas cap to relieve the pressure. T your gauge into the regulated fuel line. Put the fuse back in and then start it up.

QFT...run it till it dies, if not you will have fuel spray.

Just an FYI you will still have fuel leaking even with no pressure, be prepared.

It'd be a good time to go to a Z32 fuel filter or at least replace your current one.

JRas · 01-23-2009, 12:48 PM

pull the fuel pump fuse
start the car
wait for it to stall
open the gas cap
undo hose/s

nrmskate · 01-23-2009, 01:06 PM

I already replaced the fuel filter.

I got the OEM 240 one.

I didn't know which z32 one to get, TT or N/A

nrmskate · 01-24-2009, 11:01 AM

Okay, well, I go to use the Fuel Pump pressure kit we have.

And every single tester kit/gauge, only reads to like 10-12psi.

And my engine default is like 34-40psi.

slider2828 · 01-24-2009, 11:10 AM

Yah that is low pressure.... Change fuel pump

nrmskate · 01-24-2009, 11:13 AM

No no no, im saying the gauge only goes up to 10-12, like, there is nothing past that, and it obviously maxes out the gauge.

nrmskate · 01-24-2009, 11:14 AM

Like this.

slider2828 · 01-24-2009, 05:18 PM

Wow ergh... That ain't going to work... anything from autozone?

nrmskate · 01-24-2009, 05:31 PM

went there, aint nothin man.

Only had one that read up to 10psi.

they had like, tire gauges that went up to 100psi and wanted to try that, but the guy at autozone said it wouldn't work.

alkemyst · 01-24-2009, 08:46 PM

Quote:

Originally Posted by nrmskate

went there, aint nothin man.

Only had one that read up to 10psi.

they had like, tire gauges that went up to 100psi and wanted to try that, but the guy at autozone said it wouldn't work.

autozone has them, but they are clueless. I picked one up from amazon.com cheap.

slider2828 · 01-24-2009, 08:51 PM

I dunno check your coilpacks... thats easy do that first.

racepar1 · 01-24-2009, 09:08 PM

All you have to do is:
1- remove the fuel pump fuse and start the car to relieve the pressure
(I usually just skip that step personally)
2- remove the fuel cap to relieve the pressure in the tank
(this will prevent fuel from coming out of the fuel line once you remove it)
3- loosen the clamp on the hose coming out of the fuel filter
(in the engine bay)
4- remove the hose that you just loosened the clamp on
5- use a t-fitting and a small piece of fuel hose to install the pressure guage
6- re-install the fuel pump fuser
7- start the car and read the pressure on the guage

projectRDM · 01-24-2009, 10:04 PM

Quote:

Originally Posted by nrmskate

I already replaced the fuel filter.

I didn't know which z32 one to get, TT or N/A

They're the same.

windshieldwiper · 01-24-2009, 11:38 PM

fuel injected cars have higher pressures.

Quote:

Originally Posted by nrmskate

Like this.

alkemyst · 01-24-2009, 11:38 PM

i wanted to add, if you are looking for a fuel pressure gauge I bought one designed for schraeder valves and then a schrader to barb attachment. I can use the gauge for either set up now. I picked up a couple feet of hose as well...the stock setups are a bit short for our cars.

duffman1278 · 01-24-2009, 11:43 PM

You can make one, thats what I did.

nrmskate · 01-25-2009, 10:31 AM

Where did you get the gauge from ^

duffman1278 · 01-25-2009, 12:19 PM

I got that from my dad, he had an extra one at his job.

alkemyst · 01-25-2009, 12:26 PM

all you need is a 1/4" block to double barbed fitting and any guage to duplicate this. It's a really easy setup to do. I never thought about just building one and leaving it inline.

I bought this:
Amazon.com: Actron CP7818 Fuel Pressure Tester Kit: Automotive

and then some of the parts at a napa for under $10 to make
Amazon.com: Actron CP7838 Professional Fuel Pressure Tester: Automotive

01-23-2009, 12:02 PM	#1
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	checking Fuel Pressure Well, the problems I have been having lateley leave me and my mechanic to believe that my problem could be fuel related. He asked me to do a fuel pressure test to check it out. So, I just wanna make sure im doing it right. -Unplug Fuel Pump Relay -Open gas cap -T clamp with press gauge -Install fuse back in and shut gas cap -Ignition "on" and read the gauge? I think it's right, just wanna make sure everything looks good before I possibly fuck something up. Thanks.

01-23-2009, 12:48 PM	#5
JRas Zilvia FREAK! Join Date: Jul 2007 Location: Arizona Age: 35 Posts: 1,503 Trader Rating: (2) Feedback Score: 2 reviews	pull the fuel pump fuse start the car wait for it to stall open the gas cap undo hose/s __________________

01-24-2009, 11:10 AM	#8
slider2828 Post Whore! Join Date: Oct 2004 Location: San Francisco, CA Posts: 5,998 Trader Rating: (13) Feedback Score: 13 reviews	Yah that is low pressure.... Change fuel pump __________________ Turn and Burn!

01-24-2009, 05:18 PM	#11
slider2828 Post Whore! Join Date: Oct 2004 Location: San Francisco, CA Posts: 5,998 Trader Rating: (13) Feedback Score: 13 reviews	Wow ergh... That ain't going to work... anything from autozone? __________________ Turn and Burn!

01-24-2009, 08:51 PM	#14
slider2828 Post Whore! Join Date: Oct 2004 Location: San Francisco, CA Posts: 5,998 Trader Rating: (13) Feedback Score: 13 reviews	I dunno check your coilpacks... thats easy do that first. __________________ Turn and Burn!

01-23-2009, 12:37 PM	#2
Otto347 Nissanaholic! Join Date: Dec 2008 Location: Upstate NY Age: 44 Posts: 1,699 Trader Rating: (15) Feedback Score: 15 reviews	Sounds right, it should build up the correct pressure (or not) then go from there. I usually just get a towel and wrap it around the fuel line where im taking it apart. Pop it off and the fuel goes on the towel but guess the extra caution doesnt hurt.

01-23-2009, 12:39 PM	#3
sbc Leaky Injector Join Date: Jul 2005 Location: Canada Posts: 75 Trader Rating: (2) Feedback Score: 2 reviews	With the car running pull the fuel pump fuse and let the engine die out. Open the gas cap to relieve the pressure. T your gauge into the regulated fuel line. Put the fuse back in and then start it up.

01-23-2009, 01:06 PM	#6
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	I already replaced the fuel filter. I got the OEM 240 one. I didn't know which z32 one to get, TT or N/A

01-24-2009, 11:01 AM	#7
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	Okay, well, I go to use the Fuel Pump pressure kit we have. And every single tester kit/gauge, only reads to like 10-12psi. And my engine default is like 34-40psi.

01-24-2009, 11:13 AM	#9
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	No no no, im saying the gauge only goes up to 10-12, like, there is nothing past that, and it obviously maxes out the gauge.

01-24-2009, 11:14 AM	#10
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	Like this.

01-24-2009, 05:31 PM	#12
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	went there, aint nothin man. Only had one that read up to 10psi. they had like, tire gauges that went up to 100psi and wanted to try that, but the guy at autozone said it wouldn't work.

01-24-2009, 09:08 PM	#15
racepar1 Post Whore! Join Date: Jul 2007 Location: Simi Valley, CA Age: 41 Posts: 9,006 Trader Rating: (106) Rides Gallery: racepar1 Feedback Score: 106 reviews	All you have to do is: 1- remove the fuel pump fuse and start the car to relieve the pressure (I usually just skip that step personally) 2- remove the fuel cap to relieve the pressure in the tank (this will prevent fuel from coming out of the fuel line once you remove it) 3- loosen the clamp on the hose coming out of the fuel filter (in the engine bay) 4- remove the hose that you just loosened the clamp on 5- use a t-fitting and a small piece of fuel hose to install the pressure guage 6- re-install the fuel pump fuser 7- start the car and read the pressure on the guage

01-24-2009, 11:38 PM	#18
alkemyst Zilvia Addict Join Date: Oct 2003 Location: Florida Age: 53 Posts: 868 Trader Rating: (0) Feedback Score: 0 reviews	i wanted to add, if you are looking for a fuel pressure gauge I bought one designed for schraeder valves and then a schrader to barb attachment. I can use the gauge for either set up now. I picked up a couple feet of hose as well...the stock setups are a bit short for our cars. __________________ Now my Kensai, I curse you to be a Ronin and with the my remaining spirit I, beseech Chimata-No-Kami, to have you wander through time and distance lands, seeking a new master.

01-24-2009, 11:43 PM	#19
duffman1278 Post Whore! Join Date: Apr 2007 Location: Covina Age: 36 Posts: 2,844 Trader Rating: (8) Rides Gallery: duffman1278 Feedback Score: 8 reviews	You can make one, thats what I did.

01-25-2009, 10:31 AM	#20
nrmskate Zilvia Addict Join Date: May 2008 Location: IL Posts: 977 Trader Rating: (9) Feedback Score: 9 reviews	Where did you get the gauge from ^

01-25-2009, 12:19 PM	#21
duffman1278 Post Whore! Join Date: Apr 2007 Location: Covina Age: 36 Posts: 2,844 Trader Rating: (8) Rides Gallery: duffman1278 Feedback Score: 8 reviews	I got that from my dad, he had an extra one at his job.

01-25-2009, 12:26 PM	#22
alkemyst Zilvia Addict Join Date: Oct 2003 Location: Florida Age: 53 Posts: 868 Trader Rating: (0) Feedback Score: 0 reviews	all you need is a 1/4" block to double barbed fitting and any guage to duplicate this. It's a really easy setup to do. I never thought about just building one and leaving it inline. I bought this: Amazon.com: Actron CP7818 Fuel Pressure Tester Kit: Automotive and then some of the parts at a napa for under $10 to make Amazon.com: Actron CP7838 Professional Fuel Pressure Tester: Automotive __________________ Now my Kensai, I curse you to be a Ronin and with the my remaining spirit I, beseech Chimata-No-Kami, to have you wander through time and distance lands, seeking a new master.