bd0nalds0n

When I put the Andy Keel supercharger kit on my car, I bought either Nordskog or Cyberdyne gauges for boost, fuel pressure, and o2 guages. My fuel pressure sender has given up the ghost, Nordskog seems to have gone out of business, and I can't find a replacement Cyberdyne gauge that's rated 0-100 psi, just up to 16psi. The sender is two wire.

Anyone have suggestions about where I might find a compatible replacement? I was able to find a two wire sender, but the pressure rating is significantly higher, and the gauge interprets the output as being somewhere around 90PSI which I know is inaccurate.

I'd rather find a compatible sender that allows me to keep the gauge for color/continuity purposes. I also don't really want to spend ~$250 for an Autometer gauge kit from Jeg's/Summit.

Any advice/shared experience appreciated

GregBBRD

Brian, does the bad sender give you any clue about it's range, stamped into the sender?
I don't understand why you would need two wires for a pressure sender. Are they both needed/used?

Bosch makes generic pressure senders for 0-100 psi, as well as 0-5 bar, and 0-10 bar.

bd0nalds0n

Thanks Greg. Yes they're both used. The wiring loom has one red and one black wire. With the black wire disconnected, the gauge reads zero.

76FJ55

I would assume it uses on for the ground path . The gauge is probably reading a differential voltage across the sensor. A single wire sensor would probably work if the sensor body is grounded and the black wire from the gauge is also connected to ground.

GregBBRD

Yes, that would make sense. Bosch (and others) ground the sensor body, instead of running a separate ground.

That should open up a plethora of different senders, for you, Brian....

dr bob

Just make sure the gauge itself can work with the grounded leg. Many industrial gauges operate with sensors based on differential with no reference to some mysterious remote and noisy ground-return path. When I see a differential sender in a car, I also start looking at industrial transducers. I'll also share that simple differential transducers are very bulletproof. Are you completely sure that the transducer itself is the fault? The connecting cable is typically twin-axial, two conductors twisted inside a braided shield, with the shield grounded only at the gauge end, and no other ground connection at the transducer end. The twisting can reduce induced noise on the signal carried by the two inner conductors, while having the shield grounded at the source of the sensor current (in this case the gauge) prevents ground differences ("ground loop" in audio is a good example) from being induced onto the inner conductors. Hopefully you can see that having one side of the transducer grounded locally will risk lots of problems if the circuitry in the gauge itself isn't set up to handle that condition.