I have a code for a fuel pressure sensor..I have one ordered.. only $26 .. figured I put a new one….where on my 2013 express 5.3 is it.. it’s not a TANK pressure sensor…some say on the fuel rail…some say under the drivers seat on fuel line….where should I look…thanks

 

post the code please

 

The code is p0191.

 

I meant the whole code. So, it's P0191: Fuel Rail Pressure (FRP) Sensor Performance
DTC is set when a pressure change of at least 4psi is not detected when the pump is turned on.

Before throwing parts at this, you'll want to try some basic troubleshooting. The sensor could be working perfectly fine.
I would put a gauge on the fuel rail to verify the pressure. I would suspect the pump before this sensor.

Use a DMM to test if you get a good 5V reference signal between pin 3 (Brown) and ground. (ignition on)
This is an underbody harness so it exposed to the weather, debris etc. Check for moisture/corrosion in the connector. Try unplugging/replugging it a few time to wipe the terminals, and apply some dielectric grease.


Did you order an OEM part? This is important for sensors.

You can find drawings here:
http://chevygmcvans.com/viewtopic.php?t=11113

Or more up-to-date ones on gmupfitter.com

 

Seams like a lot of info for a simple question… it has fuel pressure at the rail… I ordered a GM oem part number from Amazon.. thanks for the diagram for the location .. that’s all I really needed….

 

It's still a little early to celebrate, don't you think?

I'm trying to provide ALL the information that you (or anyone who might be looking in the future) might need to solve the problem.
I've NEVER had anybody complain about getting too much information, so that's a first.

Great. You didn't provide it, so I had to mention it.
Also , squirting a bit of fuel out the valve doesn't constitute measuring properly with a gauge and monitoring for pressure changes.

buyer beware ... lots of Chinese counterfeit GM parts on Amazon.

You're very welcome