Gas guage acting strange

[318ti97]

My gas guage tends to suddenly drop all the way to "nil" and jump back again. At time it sticks in the "nil" position until I bang on the dash board right above it. Then, it tends to go back to the correct reading.

Any help..........

Thanks!

[madfronter]

That was happening to me since I bought my car in 2000. My fuel pump just died on me and when it was replaced it fixed the problem. The fuel pump and the sending unit are all one unit.

[318ti97]

How much did it set you back?

[madfronter]

I think it cost about $300.00 for parts and labor.

[bullmand]

This is a common problem on these cars. The contacts on the sending unit get dirty and cause weird gauge behavior. Run a couple of bottles of the Red Line fuel system treatment through there and it should start behaving normally. That should cost you about $14, plus two tanks of gas.

[cali-ti]

i would try running some fuel system cleaner through the tank.

[thark5]

I had this happen with my 97 not too long ago; check the fuse box. There are two fuses that protect the dashboard cluster, and one of them had blown. The fact that some current was getting through was causing the needles on the temp and fuel guages to bounce back and forth. Very disconcerting!

Tom

[318ti97]

Thanks, I will check it out this eve. Hopefully that is all what is wrong with it.

[Etienne]

The ti actually has 2 little bobble things in the tank. One is connected to the fuel pump, the other is on its own. The one that is by itself is not that expensive to replace, so if running the cleaner through doesn't work, replace that one first. I had the same problem on mine, and even Red Line didn't help. Replacing the bobble has cleared up the issue.

[yeehawbob]

I have had that problem with a totally different cause.
I used to store spare change in the ashtray by the Cig lighter. I saw my gauges go bezerk some times and the every now and then the fuse(s) will blow out. I thought I had major electrical problem but then by chance/luck I started to clean out the ash tray and then I noticed that a few coins had gone under the removable tray. I took out the whole thing and found a quarter stuck next to the Cig lighters exposed wire contacts. I took out all the coins from under the tray and I do not store anything metallic in there and since then I have had no problems at all.
Please check to see if you have a similar issue too.
Cheers!
Bob

[Newbomb Turk]

Nov 12th 2019
Has anyone had this EXACT problem since 2006? Fuel gauge intermittently going to zero (reading empty) and back when you bang on the dash? Just fuel gauge only? Against my better judgement, I replaced the fuel pump/sender assembly, even though banging on the dash would make it work for a minute. I replaced it because the car was approaching 190k anyway. After that, I went with my gut and replaced the dash cluster with used one instead of replacing the fuel gauge driver motor itself. There are three plug in connections on the rear of the cluster. Two on the left, one on the right. I’ve wiggled each, added dialectric grease to the plugs. The blue one seems to be one with fuel gauge within it. Tugged on each wire of each connector looking for a loose wire. Nothing... grrrr.
I’ve read the posts about adding Red Line fuel treatment, the fuses and the rest. It’s my sons car, I’m too old for this crap and it’s to damn cold out to be F’ing with this.
Anyone know what to look for at this point? Any new fixes?

[paul somlo]

Originally Posted by Newbomb Turk

Nov 12th 2019
Has anyone had this EXACT problem since 2006? Fuel gauge intermittently going to zero (reading empty) and back when you bang on the dash? Just fuel gauge only? Against my better judgement, I replaced the fuel pump/sender assembly, even though banging on the dash would make it work for a minute. I replaced it because the car was approaching 190k anyway. After that, I went with my gut and replaced the dash cluster with used one instead of replacing the fuel gauge driver motor itself. There are three plug in connections on the rear of the cluster. Two on the left, one on the right. I’ve wiggled each, added dialectric grease to the plugs. The blue one seems to be one with fuel gauge within it. Tugged on each wire of each connector looking for a loose wire. Nothing... grrrr.
I’ve read the posts about adding Red Line fuel treatment, the fuses and the rest. It’s my sons car, I’m too old for this crap and it’s to damn cold out to be F’ing with this.
Anyone know what to look for at this point? Any new fixes?

I don't have the answer, but you're not alone - I've had the same issue for several years now. Gas gauge goes to zero, bang on the instrument panel, goes back to normal. Most likely an issue with the gauge itself, a connector inside the cluster, or an intermittent solder joint in the cluster.

It's a harsh environment for solder joints; vibration and temperature cycling.

[macilona]

FYI.......I fill up using the trip odometer. Set it to 0 when I fill up, and stop for gas again when it gets to 300 or so. (The actual range on a tank is around 400 miles) Not worth the effort or money to fix the gauge problem!

[paul somlo]

Originally Posted by macilona

FYI.......I fill up using the trip odometer. Set it to 0 when I fill up, and stop for gas again when it gets to 300 or so. (The actual range on a tank is around 400 miles) Not worth the effort or money to fix the gauge problem!

Yep, same here - I know that I'm good for about 420 miles on a tank; when I get close, I fill it up, regardless of what the gas gage says.

[Newbomb Turk]

Paul, it’s not the gauge. Instrument cluster is new. I’m betting on a bad pin in the blue connector on the back of the cluster head.