I have read most of the older posts regarding gas guage problems (seem most probs were bad grounds). I have replaced my guage with an Autometer 4317 (0-30 ohm) and connected it to the old guage wire from the tank. The Autometer guage has 3 connections - ground, guage power from ign and the sender(I connected the old wire here). The guage reads full when ign is turned on. Can I use the old sender unit for this guage? I assumed I could. Anyone have any suggestions? Thanks Roger
I disconnected the sender wire at the tank....meter dropped to 'empty'. Put it back on, it goes to 'Full'. I have good ground from the tank to frame (checked that various ways) and frame to guage, etc. I put an ohm-meter across the 'sender' connection on the tank and ground...meter constantly reads 33 ohms(is this a good way to measure the resistance on the tank unit?). The tank has about 1/8-1/4 full of gas. I'm thinking now, that the sender in the tank is not working between 0-30 ohms. Am also wondering how the old stock gas guage worked - it seemed to work ok and good on fuel level in the tank. Any suggestions would be appreciated. Roger
Make sure yor remove the wire from the sending unit before making this measurement. With the wire removed and your 1/8 to 1/4 full tank you should read somewhere less than 10 ohms. Our fuel gauge systems expect 0 ohms at the sensor when empty and 30 ohms when full. Any reading over 30 ohms will just be fuller than full. Assuming a correctly operating system, disconnecting the gauge to sending unit wire at the sending unit and turning on the ignition switch should result in a full reading from the gauge. Touching the wire to ground should result in an empty reading at the gauge. Roger, your system sounds like it is operating backwards from this. Does the Autometer gauge instructions say that the 0 ohm load on the gauge should result in an empty reading and 30 ohms full? Personally, I've never heard of a 0-30 fuel gauge system that worked in the opposite direction, but that doesn't mean there couldn't be such a beast.
does your gauge match your sender? If you have a 0-30 ohm sender you need a 0-30 ohm gauge....Big Tim
Sender Problems?? I would go to the Autometer site and look to see which sender you would use for the gauge. Then you will know what you need to do for it. It will also tell you what the reading is for full/empty. I would check for you but I don't know which gauge you have. I think they use a 40 to 240 ohm sender but that may be wrong for the gauge you have.
Autometer-sender problems Autometer does document that this guage I have (ATM-4317) does use 0 ohms for empty and 30 ohms at full. I removed both wires at the tank (sender and ground) and put ohmeter between sender and tank. I get around 35 ohms (measured lots of times and 'rocked' the truck and see the ohms vary some). I don't think I can ever get this guage to work when the sender reads + 30 ohms. I will check with Autometer why the guage reads 'full' when the 'S' connection is grounded and 'empty' when the 'S' connection is disconnected (I think should be the opposite). I noticed when I ran the stock guages, the gas level guage would be really 'jerky' as the truck moved down the road - enough quick movement to think there might be something amiss. Thanks for all the responses. Roger
Sounds right. You should have left the sending unit ground attached just in case the tank itself wasn't supplying ground, but probably makes no difference. Pull the sending unit from the tank. Attach one meter lead to the post and the other lead to one of screw holes. Manually move the float up and down. Should read around 30 ohms up and around zero ohms down. I agree. Maybe the wrong gauge was put in the package. My stock gauge bounces around +/- at least a quarter of a tank while driving. These gauges do not have damper systems like modern vehicles.
Autometr / Sender problems Thanks Bill for the posts... Autometer determined that my gauge was built incorrectly - has the incorrect internal parts. Looking inside, thru the light connection, you can see the internal part number. Autometer said that I had the internal parts for a 240 ohm empty - 33 ohm full, even tho the other labels and the front plate of the gauge has the 4317 labels (the 0-30 ohm gauge). I have asked for a replacement. I suppose some of the best companies put out a bad product from time to time. I also pulled out the tank sender. Its bad - the internals are so loose and rickety, I could not get a good ohm reading on the bench. Its just worn out. Just ordered a replacement. Roger
gas gauge I finally have this resolved. I replaced the sender in my tank and have my 3rd autometer gauge installed (first 2 were built incorrectly by the vendor, according to their tech support). Roger
Good deal ! I'd be sure to write this vendor some sort of thank you note as few vendors these days will stand behind defective products .
I have had a problem with my Autometer gas gauge. It will only read 1/2 tank when full and empty when at half. I pulled my sender and noticed it was for the new style sender with the fuel line on top. I replaced it with the correct 53' sender and it still reads 1/2 at full. I noticed the new sender was 60 ohms. So if I'm following this thread right, I probably have a 30 ohm gauge from Autometer as well. Is there some kind of resistor, adapter or capacitor that could change the OHMs from the sender? Thanks, Flashlight
Not really. You might be able to get it a little closer, but it will never be near correct if it doesn't match the gauge.
