Gas guage quite working

[tcmustang]

My gas guage quite all of a sudden. One day it worked , next day nothing. Is there a sending unit outside of the tank. I am contemplating droping the tank . All other guages work, checked all fuses. What else? Thanks

 

[88vert]

You are probally going to have to drop the tank.I am pretty sure the sending unit is in the tank There are other options,like cutting a hole in the floor.

 

[sirgeorge]

I have a '92 and had to drop the tank to get to the sending unit.

 

[Commtech]

Mine has been out for years, I use the Trip Counter and keep track of milage.

 

[Maniak]

First, check for a broken wire... Ground the wire that goes from the sending unit to the gauge. If it gauge reads full, then the sending unit is the problem..

In that case, drop the tank is in order.. and the sending unit/fuel pump is really 1 big piece.

I've been using my trip meter for the last 100k miles.. Its been great until recently.. Now my trip meter isn't reading correctly.. (between 10-20% off)..

Time to fix both my drive gear (speedo gear) and my fuel pump/sending unit... (been putting it off long enough)

~Mark

 

[a1991owner]

Mine quit months ago lol, I have been using my milage as a means of measuring gas consumption. If you don't have the time or money to drop your tank, figure about 200 - 250 miles will get you one tank (At least that is what mine is)

 

[explorerjoe]

I had the same problem when I bought my 94 Ex. It had 93K on it so replacing the pump was essesntial for reliablility on the back roads. However I found that this DID NOT fix the fuel gauge. If you pull the instrument cluster, you will see a small printed circuit board. This board monitors the resistance at the tank then sends the correct signal to the gauge. I suggest you pull the pump/sending unit and check its operation using a multi-meter. I believe the range on my new unit varied from aprox. 19ohms to about 280ohms. I found the replacement board at a bone yard, paid $20 for it, new cluster from ford was thousands.. This is just one more place to look. I did the mileage thing for a while, but when you start going off road and go into 4low then average 6mph for 2 days looking a a fuel gauge that always read empty can be unnerving.

 

[Opera House]

Sender resistance

is 15 ohms empty and 170 ohms full. This is reverse of what many people think. If you open the connector, the gauge reads full. Shorting the sender makes it read empty.

 

[explorerjoe]

I don't remember which one was empty/full. If you are able to get gauge deflection by grounding the lead, then I would say its in the sending unit. When I was trouble shooting my system, I received no deflection when grounding and traced it to a fried resistor on the board I mentioned. Have you tried to use a multi meter on the sending unit to see if you get a change in resistance as you move the float? My original unit seemed to work fine in this respect, but was broken (showed spots of infinite resistance) in numerous places. One more place to look is the float itself, if it doesn't float it will always read empty. Mine was a small soldered barrel that snapped in place. If I remember right, it was really cheap to replace through Ford. If not I got a good one for ya..

 

[JimT]

I'm on ranger number four and '91 Explorer number 1. Gas gauge just failed on the EX. ON one of the Rangers, when the gauge went dead I dropped the tank and found that the float had disintegrated. So....no float....no indication other than empty. BUT!!!!

Here's a quick test/tip about the gauge. With the key off no power to the gauge cluster lock you eyes on the gas gauge. It may "appear" to show empty but now turn the key on and whai for a slight drop in the indication. If the needle moves I'll bet that your gauge is OK and that there is a proplem with the information from the sending unit and when you drop the tank and pull the unit don't be surprised if you have to fish aroung the bottom of the tank for float guts.

Jim T
skyepuppie@aol.com