I need to test the fuel pressure on my car so I went to buy a fuel pressure tester $40 at Advance Auto. And it was the kind for multi port fuel injection. It had a thing you would screw into the system to check the pressure easily. Our cars don't have that. So if I used it I would have to cut the end off. Void the warrenty.

So I went to lowes. I bought a dial gauge that is used to find water pressures. Small, but it runs to 100PSI. It has 1/4" NPT. Then I got a 1/4" NPT three way spliter. One part of the T has the Gauge in it. The other two have a 5/16" barbed connector. This lets you slip on the fuel hoses and then clamp them.

It cost me $10 to make this. Hope this helps others needing to check fuel pressures. This setup could also be used to check oil pressure. I hope to get some pictures soon.

JAmes

 

Hey, I bought a fuel pressure tester at Pep Boys, had the same problem, bought the same T at my local ACE hardware, except that there is a fitting for that T that allows you to screw the fuel guage fitting directly to it. Some kind of air fitting, can't remember the name exactly, but it worked perfectly without any guage modification, and I like the vent feature that the guage came with.

Irv, Keith's dad

 

Here are the pictures of my fuel tester. The image below is what how it was to test the pressure going to the fuel rails. Just unplug the hose closest to the front of the car and plug into the barbed connector. Then get some extra hose and run that to the fuel connection to the rails. Don't forget hose clamps!



This is the way it was to test the pressure coming from the fuel pump. Just take the fuel hose coming from the fuel filter then plug it into the gauge.



The barbed connectors are 5/16" barbed connectors. The threads are all 1/4"NPT.

This cost me $10. The ones at the stores are $40.

James

 

Where would you mount this gauge at? I went out and bought the parts to make the first one(inline), and want to leave it in the car. Would that be wise, as long as it was secure?

Thx

 

That's basically what it tells you to do in the FSM.

Ideally you want the gauge to be visible while driving (temporarily taped to the wiper arm or something) to ensure fuel pressure isn't dropping off at high load.

 

Not sure about leaving it in the car. The gauge I got was used for water. So, I do not know if the gauge can handle a protroleum product. However, there was no warning on the gauge.

Just would hate for it to spring a leak.

James

 

wouldn't an electric/digital guage be a bit nicer inside the cockpitthan a mechanical gauge strung outside the hood?

 

That's obviously a lot more expensive. This set-up is fine for testing purposes.

 

so if i wanted that guage in my cabin, could i just use hose to go inbetween the T fitting and the guage ....

would that cause miss readings in the guage? seeing as how the guage would obviously be further from the t fitting as the picture shows???

and would that be bad to do as i assume gas would be flowing into the tube that i would use the extend the guage into the car?

 

dp

 

You cannot do that, as it is illegal to run fuel lines inside the cabin. You'd need to buy a fuel pressure isolator, which transfers the fuel pressure to a water-filled line that you run into the cabin.
Other than what I said above, this is no different to running boost or oil lines to gauges.

 

thanks mang

 

Try JC Witney's for a cheap fuel presure tester. They are cheap but for the few times you actually use it, it works fine. It also has all of the adaptors for different makes so it can be used on any car.

 

As said earlier, you don't want fuel lines in the cockpit for safety reasons. The pressure gauge taped to the windshield idea works, but I recently stumbled on an inexpensive alternative: Surplus 0-100 psig pressure sensors from Ebay. They are a cheap ($14 for two), rugged, and precise method of measuring pressure in that range, and provide an electrical output signal so you can simply run wires to the cockpit.

The seller (no affiliation, BTW) seems to have a boat load of these things, as I bought 10 a few months ago, and he is still selling them. Here's the link:

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2471476300

The sensor needs a +5V supply and ground, and returns a 0-5v signal proportional to pressure. The 0-5v signal can be read by a voltmeter in the cockpit, or fed into a standalone ecu as an auxilliary input for datalogging purposes. The stock ecu sends 5v reference to the MAP sensor and TPS, so either of these could be spliced to power the unit. The sensor body is 1/4" NPT male, so fitting to your fuel system is pretty straightforward.

 

Do you have any pictures of how you set that voltage sensor up? Is there a plug that you could buy to fit on top of the sensor, and make wire connections easier?

Thx

 

smith88,

I don't have pictures handy at the moment, but I just used a 1/4" NPT tee, with two barb fittings on opposite ends, and the transducer on the remaining branch. The end result is just like Wankel7 posted, only with the sensor in place of the gauge.

The connector and pins are standard Packard parts. Rumour has it GM uses the same connector to power the A/C clutch, but I haven't verified this. The datasheet for that sensor is here. I bet they were 10x the price when new.

http://www.sensor.ru/AER/DATA/4000pc.pdf

 

thanks, this is just what i needed! i love this cheap tools/tricks you guys come up with