Fuel gauge still not working, What am I missing? Options

[john77]

Since you have the sender out, go ahead and invert it while measuring the resistance on the 2 pins. You should read 90 ohms.

Now, put the sender right side up, you should read 0 ohms. Slowly insert the sender back into the fuel tank. You should see the resistance rise. With it all the way down, you should read 70-80 ohms, if not,,try shaking the sender.

With it fully inverted 89.9, with it right way up 2.6.

Lowering it slowly did nothing, nor did shaking it around, it just stayed at 2.6.

Pushing it in fast it rose to 40 and then dropped back to 2.6.

How does this make any sense when it worked fine in water?

[john77]

The website agrees with timothy_nd28 that the sender should read 0 Ohms when empty.

This is exactly the same as grounding the sense wire to the car GND.
So without the sender in the picture at all, what does it read if you hook:
+12V to +12V
GND to GND
Sense to GND

It should read empty.
Unhook the sense wire (open) and it should read Full.

If the gauge does not do that it is broken or the description of the unit from the website is wrong.

It does nothing in either of those scenarios. So yes, the gauge is now also broken.

[timothy_nd28]

Yah, something isn't right with that sender. If it wasn't so new and possibly under warranty, I would say take it apart. Get on the phone with them, maybe they will take all of it back.

Why are you using an aftermarket sender and gas gauge? Does your old combo gauge not work?

[john77]

Yah, something isn't right with that sender. If it wasn't so new and possibly under warranty, I would say take it apart. Get on the phone with them, maybe they will take all of it back.

Why are you using an aftermarket sender and gas gauge? Does your old combo gauge not work?

It's a 6 conversion with a 2.7RS. The guy that built it swapped out the gas gauge for a 911 oil temp/oil pressure gauge.

The sender and gauge aren't new, the set up just wasn't working when I bought the car. So I could take it apart, I'd just need to find a plate to cover the hole in the tank... And probably increase my skill level...

I'll give the guy a call Monday and if my only option is to replace them I'll consider taking them apart.

[timothy_nd28]

Yah, something isn't right with that sender. If it wasn't so new and possibly under warranty, I would say take it apart. Get on the phone with them, maybe they will take all of it back.

Why are you using an aftermarket sender and gas gauge? Does your old combo gauge not work?

It's a 6 conversion with a 2.7RS. The guy that built it swapped out the gas gauge for a 911 oil temp/oil pressure gauge.

The sender and gauge aren't new, the set up just wasn't working when I bought the car. So I could take it apart, I'd just need to find a plate to cover the hole in the tank... And probably increase my skill level...

I'll give the guy a call Monday and if my only option is to replace them I'll consider taking them apart.

Consider purchasing a triple or quad gauge, it would look better IMHO. IF the sender is old, there is a possibility that the float somehow got saturated full of gas. This would explain why it doesn't float in gas, but only floats in denser fluids like water. I'm pretty sure the whole car is ruined now, please pull the engine and send it to me (IMG:style_emoticons/default/chowtime.gif)

[bandjoey]

I'm no expert here but. You can probably get a working original float from someone here. Cheap. Why not get one and use it? At least it'll eliminate one part of the problem. Just a thought. Good luck. (IMG:style_emoticons/default/sawzall-smiley.gif)

[john77]

Yah, something isn't right with that sender. If it wasn't so new and possibly under warranty, I would say take it apart. Get on the phone with them, maybe they will take all of it back.

Why are you using an aftermarket sender and gas gauge? Does your old combo gauge not work?

It's a 6 conversion with a 2.7RS. The guy that built it swapped out the gas gauge for a 911 oil temp/oil pressure gauge.

The sender and gauge aren't new, the set up just wasn't working when I bought the car. So I could take it apart, I'd just need to find a plate to cover the hole in the tank... And probably increase my skill level...

I'll give the guy a call Monday and if my only option is to replace them I'll consider taking them apart.

Consider purchasing a triple or quad gauge, it would look better IMHO. IF the sender is old, there is a possibility that the float somehow got saturated full of gas. This would explain why it doesn't float in gas, but only floats in denser fluids like water. I'm pretty sure the whole car is ruined now, please pull the engine and send it to me (IMG:style_emoticons/default/chowtime.gif)

Haha, I have a guy crating the engine as I type.

There's a chance the sender was sitting in gas for a long time - that sounds like a very plausible explanation. Is that something I could possibly take apart and reseal?

Never knew you could get triple/quad gauges, any idea who makes them? It would certainly look cleaner. The only bitch is that the builder screwed the holder for the new gas gauge straight into the front of an otherwise perfect dash. Well, otherwise apart from the hole they then cut in it to run the wires into the back of the gauge cluster. So if I do clean it up with a triple gauge I get to stare at two screw holes...


Edit: I just used this new thing called google and found a couple of places: North Hollywood Speedometer and New Vintage gauges. Not sure how much $$$$ they are, so f anyone has any other recos feel free to chime.

[john77]

I'm no expert here but. You can probably get a working original float from someone here. Cheap. Why not get one and use it? At least it'll eliminate one part of the problem. Just a thought. Good luck. (IMG:style_emoticons/default/sawzall-smiley.gif)

I'm not sure if they're compatible, I'd have to look into it. Good suggestion if it is though, thanks.

[timothy_nd28]

Not compatible. Porsche senders are 0 ohms full and 90 ohms empty

Your aftermarket gauge/sender set is the inverse. 90 ohms full and 0 ohms empty.

Unless you are talking about stealing a float out of the 914 sender to fix this after market sender?

[timothy_nd28]

Edit: I just used this new thing called google and found a couple of places: North Hollywood Speedometer and New Vintage gauges. Not sure how much $$$$ they are, so f anyone has any other recos feel free to chime.

These triple gauges or quad gauges do pop up time from time in the classified section. Price seems to be around 250-400 dollars. You could post a WTB ad in the classified section

or

You could consider buying this kit:
http://www.914world.com/bbs2/index.php?sho...05600&st=80

Sounds like you already have the 911 gauge for this project

[john77]

Edit: I just used this new thing called google and found a couple of places: North Hollywood Speedometer and New Vintage gauges. Not sure how much $$$$ they are, so f anyone has any other recos feel free to chime.

These triple gauges or quad gauges do pop up time from time in the classified section. Price seems to be around 250-400 dollars. You could post a WTB ad in the classified section

or

You could consider buying this kit:
http://www.914world.com/bbs2/index.php?sho...05600&st=80

Sounds like you already have the 911 gauge for this project

Thanks for the link, that triple gauge looks like a great option.

I finally got the correct sized torx bit today and was able take the sender apart. I can't see any bad connections but the circuit board has a layer of crusty dried gunk over it. Any idea what I could use to clean it off without damaging the board? For starters I was thinking of trying 99% alcohol with q-tips.

[timothy_nd28]

Cool sender, I never seen one like this. It needs to be cleaned, but I would feel terrible if I gave you bad advice which could destroy it.

If you are serious about the triple gauge, you would need a stock sender.

[john77]

Cool sender, I never seen one like this. It needs to be cleaned, but I would feel terrible if I gave you bad advice which could destroy it.

If you are serious about the triple gauge, you would need a stock sender.

Ha, yeah, that occurred to me this afternoon - I'll actually need to find a late 914 gauge and sender.

Probably for the best, this sender is driving me insane. I scraped off some of the crud gently with a razor blade and then soaked it over night. Put it back in the car today and what do you know it worked... kind of. I placed it back in the tank hooked up to my multimeter and it rose to 13.6 ohm and stayed there. Then I hooked it up to the gauge and turned on the ignition and the needle rose up past E for the first time and just stayed there.

That is, until I rebolted the gauge into the tank. And then it drop back past E, and read 2.6 ohm again on my multimeter...