1990 Festiva Fuel Gauge bad Sending Unit

[bravekozak]

According to the 1990 Festiva Car Shop Manual.

F = 7 ohms
1/2 = 32.5 ohms
E = 95 ohms

[bravekozak]

Let's have a contest. Guess the number of wraps in a Festiva EFI sender based on the picture in post #10. I guess 83. What do you guess?

[bravekozak]

I was thinking about the winding process and how the wraps get tighter toward the end to compensate for the reduction in the swing arc when the tank is full and the float is high.

It appears that the wider spaced wires when the tank is low, tend to get worn away first (greater arm movement). The tighter windings have less wear and still transmit a resistance and a fuel level when the arm gets to that position, where it stops jumping around from no resistance to resistance.

It would be good to position a mirror underneath so that as you wind the wire into the factory grooves, you could check to make sure there is no touching underneath without having to constantly do the olympic squat or flip the resistor wire board over.

[bravekozak]

Did everybody follow the revive link in post #30?

Daverham bought ten feet of 36 gauge Nichrome for $2. He used just under three feet (27.0 ohms per foot X 3 = 81 ohms). Hence the $1 fix. He alo said that the wire should be purchased in a larger quantity so that it comes in a spool instead of having sharp wraps around a piece of cardboard. 100 foot spool = $6.

His resistor board is a thin rectangle. Our Festiva resistor bars are triangular and will certainly require a much longer length. Good luck Festyboy. We are counting on you.

I am guessing, but we might need 5.5 feet of the 34 gauge wire ?

[FestYboy]

This is exactly what the doctor ordered! Thank you all! So which gauge should we purchase from this website?: http://jacobs-online.biz/nichrome_wire.htm

that's not FAIR, i've been looking for that for years!!!!!

Brave, i'll have to pull a sending unit and count the wraps. keep in mind that the ohms per inch and length in feet doesn't corrispond to the # of wraps and final sweep resistance... the #s change once you start wrapping.

[bravekozak]

That's what we are trying to determine. What is the length of one complete wrap? + How many factory wraps do you count? I will find out what the intermediate resistances are. Usually most drivers will tolerate a little inaccuracy with a full tank, but prefer high accuracy below half a tank.

[the_feist_in_festiva]

This is exactly what the doctor ordered! Thank you all! So which gauge should we purchase from this website?: http://jacobs-online.biz/nichrome_wire.htm

[bravekozak]

Festivas are 6 ohms full and 95 ohms empty.

One ohm per inch would require 95 inches or almost 8 feet. Correct?

How many wraps would we need?

[FestYboy]

yeah that's what i did. but that 32ga @ 10.6 ohm is WAY too high for as many wraps as we would need.

[bravekozak]

it's not insane, it's just 28ga 1ohm/inch wire, but i can't find any so that i can repair units for the forum.

FestYboy, how did you determine gauge and resistance? Did you use a vernier, then unwind and cut it for the ohmeter reading?

The only resistance wire, from Jacob's online, that's close is the 32ga Nichrome 60 (Chromel C)
@ 10.6 ohms/ft

Do you think that would work with a few extra wraps?
You would need 8 feet of it for 95 ohms.
Does anyone know how many feet of wire are wound on a standard Festiva sender?

[bravekozak]

If you want to try it yourself, ask Bob's Speedometer if they could just sell you the wire.


Or,
AWG Nickel Chromium (NiChrome) wire purchased from Jacobs Online (http://jacobs-online.biz/nichrome_wire.htm).


Revive a fuel sender.

[FestYboy]

it's not insane, it's just 28ga 1ohm/inch wire, but i can't find any so that i can repair units for the forum.

[the_feist_in_festiva]

I have some sending units. I think one of each?

How much do you want for one for a '90 Festiva L that's fuel-injected? I live in CA. The whole rebuilding and repairing route seems insane.

[the_feist_in_festiva]

I found someone in New York who rebuilds sending units. And I've found a bunch of other homemade fuel sending unit repair methods here and there. So I guess I'll do more research on it. But the gallon gas tank in the back sounds good too. I don't know anymore.

[eurotiva]

I have some sending units. I think one of each?