My Autometer fuel pressure guage likes to float up and down, especially when the grid heaters kick in!!! I installed a new 30lbs pressure sender and it's worse than the old one and the new one reads 2lbs higher too. I have a "T" in line close to the VP44 and a 2' remote hose to cushion the fluctuations. I'm also running a 1'8" pressure snubber. I have no idea what I'm doing wrong??? I had the guage recalibrated 3 months ago also. Any ideas or suggestions???

 

Well, this isn't very constructive but I take it this is an electric gauge? Lots of guys here don't like Autometer but I'm not one of them....I have owned tons of Autometer Sport Comp gauges over the years and never had trouble with them. They are are very accurate and they take a beating. That said, I have never owned an electric pressure gauge of any kind.....I would have to ask: Why electric? There are so many less issues with the mechanical gauges from any brand and every time there is a fuel pressure gauge problem on this board, it is electric! Are you ready for the mechanical gauge yet?

Sorry that I can't be any help....

 

Sorry guys, it's an electrical fuel pressure gauge.

 

Mine did the same from day one.ended up just geting a Juice with atd

 

A manual guage, isn't that bad news waiting to spray diesel in the cab???

 

I have an Autometer electrical gauge. So fer I have no problems and very accurate readings by comparison to the hand-held guage I had plugged in to the same port. There is bis a chance that you either have a bad guage or a bad sender. The only way to know without technical specs is to swap one out with a known good one. Have you contacted Autometer about this? I'll bet they'll be more than happy to rectify the situation. Here's a few pics of my recent install.

 

The autometer mechanical fuel pressure guages only come in 0-15 and 0-100, so if you want a 30 or 60 lb autometer fp guage you'd have to go electronic At least thats all I've found looking at their z series that matches our guages.

 

What electrical source did you tap into for the +12VDC ? I used upper cigarette lighter line for mine. I'm not sure if that would matter at all. I'ts too warm here for grid heaters to run right now so I definately don't have the same problem...

 

After re-reading the original post I too wonder what the grid heaters would change unless the gauge is not getting the required voltage to work properly from its current power source

 

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dodgediesel:

I had an "Autometer" Electric Fuel Pressure Guage in my 1996 Dodge CTD 12 valve and had the EXACT same problems/issues you are having. Repeated calls to Autometers Technical Assistance line would help initially with new sending units (one under warranty, one not), but each time the gauge would go right back to acting up as you describe.

I finally got tired of it and bought and installed a "DiPricol" 0-100lb. Mechanical Gauge with the Isolator and have had no more problems whatsoever! This gauge reads accurately and the needle sits still. I only wish I gotten it sooner!

Good luck to you.

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John_P

 

Is the plumbing in the walls of your house just sitting there waiting to spray water all over the place?
As long as you follow simple plumbing practices neither situation is likely to happen.

 

Good analogy Bill!!

I wish Autometer's FP gauge selection was a little better...but they'll work I guess!

Sounds to me like a wiring issue!

Chris

 

Make sure its grounded properly...

 

There is a large voltage drop everywhere when the grid heaters kick in... Tested the voltage, all good. Tested gauge with another gauge, same results. Tested with new sender and old sender, same results. I think I just need to go with a needle valve. I would rather have water sprayed in my house than diesel!!!

 

A needle valve would be a good place to start. Your fuel pressure probably changes with engine demand while the alternator tries to run the grid heaters..