Temp and Fuel gauges not working / IVR

[bossbob]

So, after getting it running, first thing I noticed is that the fuel and temp gauges aren't working, I've read a lot here on the IVR, but a lot of the post seem to be dated. I was wondering if there is any updates to the issue.

I guess I need to pull it out and test it????

Then possibly due the rebuild on it???

I can't see my self ponying up to buy a new one.

Thanks again,

[notoptoy]

The first, and easiest thing to do is remove, clean up the mount and replace.. On mine, it was just a bad ground and the gauges have worked perfectly ever since. After that there are multiple replacement suggestions that you can build on your own, threads abound.

[mellis18]

There is a voltage regulator under the dash that controls these gauges. My gauges did the same thing until I removed the VR and cleaned both mounting surfaces...the VR and where it contacts the mount area. After that the gauges worked great.

[bossbob]

Rustbucket made me a Solid State IVR, installed it and still no guages, he noticed the wire to the temp sender was disconnected, cleaned it up and re-installed it and temp gauge now works. As far as the fuel gauge, I guess I'll be taking the sending unit out to see whats going on with that.

[JT68]

In the trunk open up the little access panel to get to the sender. Clean the yellow wire connector and short it to ground. With the key ON the tank gauge should swing up to full. If so the gauge and wiring is functional. Clean the two terminals on the sender and it may work. If not, you know it is the sender.

If the gauge doesn't peg when shorted, its the wiring or the gauge.

[bossbob]

Well I guess the good news is that the wiring checks good. So, is there a way to fix the sending unit or do I have to buy a new unit.

[greydog]

Since you have isolated to the sender, I'd remove the sender and ohm check it. If it checks out ok you know its a connectivity isse. If not, replace it as Ive read the wires and assembly isfragile.
Dan

[JT68]

15 minutes to replace the sender or you can spend a day tinkering trying to get it to work reliably.

[bossbob]

I pulled the sender and ohm'd it out. It's either bouncing all over the place or not reading at all. Nothing consistent. I know the best plan is to replace it, but $165???

I would rather fix it if possible, any ideas?

[JT68]

I'll have to verify, but pretty sure I have one or two left at 135??

[greydog]

Jim (JT68) has "the real thing" and you can count on getting a good part from him.

If you dont care so much about originality, you can make a solid state one using a voltage regulator ic. Takes a little soldering skill but works fine.
A search for instrument voltage regulator should yield the threads.

Dan