Do I really need a Fuel Pressure Gauge?

[DIY4quality]

I believe there's value in having tools and test equipment on-hand, especially if they're inexpensive. So I'm thinking about getting a Fuel Pressure Gauge set, but not sure what scenarios it would actually be useful for.

If the fuel pressure sensor on my fuel rail is faulty (happened twice so far), it will send bad signals to the computer which get passed along to the fuel pump. The pump then creates an erratic fuel flow and pressure I can see on my OBD2 reader graph. Adding a manual fuel pressure gauge (connected to the schrader valve on the fuel rail) is not going to give me any additional info.

Are there any use cases where a gauge would be useful?

 

[atikovi]

If the fuel pressure sensor on my fuel rail is faulty (happened twice so far), it will send bad signals to the computer which get passed along to the fuel pump. The pump then creates an erratic fuel flow and pressure I can see on my OBD2 reader graph. Adding a manual fuel pressure gauge (connected to the schrader valve on the fuel rail) is not going to give me any additional info.

What makes you think a faulty fuel pressure sensor will send ANY signals to the computer? Low/no fuel pressure is one of the first things to test for on a crank no start.

 

[DIY4quality]

What makes you think a faulty fuel pressure sensor will send ANY signals to the computer? Low/no fuel pressure is one of the first things to test for on a crank no start.

As I indicated, I've had two fuel pressure sensors fail but the engine continued to run, just not smoothly and with the Check Engine light on. But certainly the sensor can fail completely with no fuel flowing and cause a no-start, that just never happend to me. I can see how the gauge would be helpful in that case. Thank you.

 

[Soft Cars]

I got one from Harbor Freight. U.S. General brand. It's been good. Make sure you Teflon tape the fittings or you will have a leak.

 

[DIY4quality]

I got one from Harbor Freight. U.S. General brand. It's been good. Make sure you Teflon tape the fittings or you will have a leak.

I got spoiled with those 20% off coupons in years past, so I don't go into HF as often as I used to. Now when they have sales, they're usually for a handful of items I don't need.

 

[Astro14]

I believe there's value in having tools and test equipment on-hand, especially if they're inexpensive. So I'm thinking about getting a Fuel Pressure Gauge set, but not sure what scenarios it would actually be useful for.

If the fuel pressure sensor on my fuel rail is faulty (happened twice so far), it will send bad signals to the computer which get passed along to the fuel pump. The pump then creates an erratic fuel flow and pressure I can see on my OBD2 reader graph. Adding a manual fuel pressure gauge (connected to the schrader valve on the fuel rail) is not going to give me any additional info.

Are there any use cases where a gauge would be useful?

That’s exactly the scenario in which you need an accurate gauge. Diagnosing low fuel pressure starts with knowing the pressure is low, and not a bad sensor.

 

[RooflessVW]

Fuel pressure gauges are invaluable for diagnosing older fuel injected cars.

On modern cars I've only used it to troubleshoot long starts

 

[vwmaniaman]

I also have the HF us general one. Saved me replacing a fuel pump on my 1990 Ford Ranger. No start condition and turned out to be ignition module and PCM. Ignition module failed the PCM. Took monhts of diagnosis. I'd rather play with my Grand daughters than work on the truck. Thats why it took me so long. Lots of diagnosis and learning time. I am not the kind to start off throwing parts at a problem.

 

[D60]

Because not all vehicles even have a sensor? And no, I'm not talking ancient stuff. I know from experience a 2014 Rogue does not and I'm ASSumimg it's a theme with all Nissans of the era.

While arguably now falling a bit more into the ancient category, Toyota thought it amusing to not provide a sensor or port on the 3.4 V6. Because I'm not in the rust belt, there are still A LOT of First Gen Tacos running around here.

But ultimately.....if you have to ask.....you don't need one? How's that sound?

 

[paulo57509]

I would say that it's a handy diagnostic tool to have (they're cheap enough). Most times I've had to use it along with other diagnostic tools, like a fuel injector tester.

 

[Bullet]

I'll be getting one this coming week. The Tacoma started having a hesitation and no codes. I haven't needed one in like 25 years, but the last time was on a 280ZX that ran fine and after a minute or two then it would have a bad hesitation. A fuel pressure gage showed the pressure was fine and shortly after it went down. Sometimes you need to be able to see the pressure while you're driving. Fuel pump can do strange things.