Huge difference in fuel psi.

[Sycostang67]

I have a GS fuel psi gauge I have been using since I installed my FASS pump 7 years ago.  Since I installed the FASS it has always hovered around 14-15psi with the sensor mounted on the pump.  When I got my Edge tuner I added a second sensor in the line 12" before the VP44 and it also hovered around the same level.  When I got the quad, I used the same sensor I was using with the Edge as it plugged right in.  A few days ago my GS gauge began reading 0psi, I pulled up the Quad fuel reading for the first time and noticed it was around 25psi which I thought was odd but figured I had pressure so I'm good.  While trying to figure out the GS gauge issue I noticed my FASS wouldn't prime with a key bump.  I start the truck and pull the fuse for the FASS and no change in pressure from the Quad.  I unplug the relay and plug it back in and now my GS gauge is back to 15psi but the Quad is now reading 50-60psi.  Through all of this the truck has run normal, starting fine, running fine, no sign of fuel starvation.  I remember a few years ago the fuse for my FASS blew and I could barely get out of my driveway.  

Edited January 14, 2022 by Sycostang67

[Mopar1973Man]

Fuel pressure sensor on the Quadzilla is fried most likely. 

 

You might review my electric gauge article...

 

You should never just have the sensor screwed directly into the fuel line. You need some distance from the snubber to the sensor to allow for fade of pulse.

Edited January 15, 2022 by Mopar1973Man

[Sycostang67]

I'm trying to figure out if the sensor Edge uses is different from the one Quadzilla uses.  Some of the vendor pics aren't the greatest but they do appear to be a bit different physically at least.  I figure I may as well order a Quad sensor since the Edge sensor should go with the tuner when I sell it.  

[Sycostang67]

Ok, I got the Adrenaline fuel pressure sensor installed last weekend and now my readings match.  I guess the sensors are internally different.  

[wil440]

You'd have  been very lucky to find 2 sensors from 2 different manufacturers used on 2 different items to output the same reading unless they were exactly the same part made by the same company with the same part number

[Mopar1973Man]

Kind of like my boost readings between ISSPro boost gauge and Quadzilla on the MAP sensor which is good to about 20 PSI after that it skews badly so actually on the ISSPro at 45 PSI I'm showing 69 PSI on the Quadzilla. Hence I know the accuracy of the stock MAP is worthless hence why I DO NOT display boost number on my Quadzilla. Changing the sensor does not fix that issue which ive already tried that too.

Edited February 10, 2022 by Mopar1973Man

[Doubletrouble]

14 minutes ago, Mopar1973Man said:

Kind of like my boost readings between ISSPro boost gauge and Quadzilla on the MAP sensor which is good to about 20 PSI after that it skews badly so actually on the ISSPro at 45 PSI I'm showing 69 PSI on the Quadzilla. Hence I know the accuracy of the stock MAP is worthless hence why I DO NOT display boost number on my Quadzilla. Changing the sensor does not fix that issue which ive already tried that too.

 Would that have something to do with the fact that the boost is capped at about 19-20psi from the factory? Anything above that would probably be above it's intended operating range.

[Mopar1973Man]

Still it all it a gauge provided, the data isn't accurate across the span. I can do the same between Quadzilla EGTs and ISSPro EGTs. There is always a possibly of differences between two guages. As for differences on EGTs is about 50 to 100 degrees varance at times even though both sensors are in the rear port an inch apart.

 

Since the a-pillar is there I use it more.