10-04-2013, 03:32 PM
Not sure if this is a question, a diagnosis, or a solution, but I wanted to post it up in case others ever experience similar conditions.
The Tip Coupe that I have as my latest project is finally on the road after a transmission swap and now that I can actually drive the car, I'm beginning to shake out all of the loose and/or bad connections. I was driving around the other day and the low fuel indicator light came on. I would have went and got some fuel, but the gauge was reading a little over half. When I got the car back on the road after the transmission swap, gauge read full, so I figured I had at least 400 miles or so. Keep in mind that I did not personally put gas in the car, so I had to assume that my buddy did when he was testing the transmission. I had only driven about 150, so some quick math set my mind at ease and figured the low fuel light was just another bad ground or possible the fuel sender had went on the fritz.
Yesterday afternoon, I pulled the fuel sender out of my parts car and out of this car so I could test and compare both units. They both tested fine with about 60ohms at empty and about 3ohms at full. Trying to only change one thing at a time for proper diagnostic procedure, I put the old/existing sender back in the car and buttoned everything up. I would disconnect connector and see light come on and gauge work, so I knew it was getting a signal from the sender to the dash. I cleaned the ground for the sender and that made the light nice and bright! Drove car home last night and all is well, but light still on.
So, it has to be a faulty gauge, right? Well, sort of........ As it turns out, my diagnostics got completed this morning when I ran out of gas! At least now I know the light works properly, the sender works properly and it is a faulty needle. It does move, just not from FULL to EMPTY! Probably very similar to those of us who have experienced the erratic temp gauge. The light should illuminate once the resistance coming from the fuel sender gets high enough to turn it on, and this is independent of the needle position. Like most people, I always thought the light came on when the needle got to a certain position. Nope, it's reading the same signal as the needle.
Now to pull the cluster and see if it is just a dirty connection. Otherwise, I'll swap it out with one of my spares. Now to get the smell of gas off of me........
So, it is possible to have the light work but not the needle. Use both pieces of info when diagnosing a faulty fuel sender. I know there are a couple of threads about the low fuel light working or not, so hopefully, this helps someone down the road.
- Darryl
The Tip Coupe that I have as my latest project is finally on the road after a transmission swap and now that I can actually drive the car, I'm beginning to shake out all of the loose and/or bad connections. I was driving around the other day and the low fuel indicator light came on. I would have went and got some fuel, but the gauge was reading a little over half. When I got the car back on the road after the transmission swap, gauge read full, so I figured I had at least 400 miles or so. Keep in mind that I did not personally put gas in the car, so I had to assume that my buddy did when he was testing the transmission. I had only driven about 150, so some quick math set my mind at ease and figured the low fuel light was just another bad ground or possible the fuel sender had went on the fritz.
Yesterday afternoon, I pulled the fuel sender out of my parts car and out of this car so I could test and compare both units. They both tested fine with about 60ohms at empty and about 3ohms at full. Trying to only change one thing at a time for proper diagnostic procedure, I put the old/existing sender back in the car and buttoned everything up. I would disconnect connector and see light come on and gauge work, so I knew it was getting a signal from the sender to the dash. I cleaned the ground for the sender and that made the light nice and bright! Drove car home last night and all is well, but light still on.
So, it has to be a faulty gauge, right? Well, sort of........ As it turns out, my diagnostics got completed this morning when I ran out of gas! At least now I know the light works properly, the sender works properly and it is a faulty needle. It does move, just not from FULL to EMPTY! Probably very similar to those of us who have experienced the erratic temp gauge. The light should illuminate once the resistance coming from the fuel sender gets high enough to turn it on, and this is independent of the needle position. Like most people, I always thought the light came on when the needle got to a certain position. Nope, it's reading the same signal as the needle.
Now to pull the cluster and see if it is just a dirty connection. Otherwise, I'll swap it out with one of my spares. Now to get the smell of gas off of me........
So, it is possible to have the light work but not the needle. Use both pieces of info when diagnosing a faulty fuel sender. I know there are a couple of threads about the low fuel light working or not, so hopefully, this helps someone down the road.
- Darryl
