Help with Isspro Gauge

[DaveHess]

I have a 0-40PSI electric Isspro Fuel Pressure gauge with the sender hooked into the port of my FASS 95. Yeasterday while running down the Interstate, the gauge went from it normal running position of about 16PSI and jumped to 40PSI. My rail pressure gauge did not fluctuate at all and worked as advertised for the remainder of my trip. When I stopped at a rest area and shut the pickup down and then restarted the truck the gauge does what it normally does but as soon as the truck started, it went to 40PSI. A normal start is the when the ignition key is turned to the on position, the gauge will drop to zero (0) and then jump up to 16PSI where it sits normally. My gut is the gauge or the sending unit bit the bullet as no fuses were blown and all the other add-on gauges are working as advertised. Could the FASS be causing this? Is the FASS 95 capable of 40PSI? How is the FASS 95 regulated? Any help here would be appreciated.



Dave

 

[BILLVO]

Unhook the wire from the sender and see if the gauge zeros out and stays at zero then ground the sender wire and see if the gauge pegs if both conditions are met the gauge is good and I would test the wire to make sure it is not rubbed through and grounding out, then most likely what you think is the sender bit the bullet.

 

[DaveHess]

Thanks Bill! I got a new address and a shop now. Call me some time.

 

[HHhuntitall]

Dead on advice. But..... Don't over look the fact that the FASS is capable of 40psi. Not saying that is the problem, but if you replace the sending unit and it still does it..... if you have a pressure guage to check the line pressure going into the CP3 pump, you might check it manually. Don't you just love electronics?! My Autometer fuel pressure guage just quit this week, too. Just hangs dead at 15psi, no up, no down, no signal through with the voltmeter.

 

[DaveHess]

Actually, I thought of just buy one of those Mr Gasket type screw in gauges to test the pump. The real PITA of all this is the gauge is in an overhead pod that is a small nightmare to deal with. I have had no problems with the pod but as soon as I start futzing with it you know what will happen.....

 

[HHhuntitall]

Nasty little boogers!! I hate the overhead guage pods. I'm always hitting them with crap, like rifle barrels, hats, and my briefcase. Somehow, I always hit the handle of my briefcase on it whenever I swing it over to put it in the passenger seat... . it's gone now, I installed a dash pod, but to each his own. Either one is a pain if you have to work on it. That's why I suggested checking the fuel pressure at the pump. If your problem is at the pump, you'll be peeved after pulling the guages... . Good luck... .