I have a 94 Dodge ram van with a 36 gallon tank and my fuel gauge is wandering all over the place. I replaced the gauge cause it was easy and still no good so now I suspect the sending unit is bad but I really do no want to drop the tank unless I have exhausted all other possibilities. Any ideas? Also, if the sending unit is bad where can I get a good one and not a cheap Chinese knock-off?

Also, for what it's worth, I recently had water in the oil and it turned out to be a tiny hole in the timing case cover behind the water pump. I pulled the heads off for no reason thinking it had to be a bad head gasket. It's running great now after replacing the timing cover and water pump.

 

If it's the sending unit, there are no other possibilities to exhaust...you live with it or you replace the sender/pump assembly. Many people have had aftermarket pumps for these van fail within 2 years. Only the OEM pumps from the dealer seem to last.

Blown head gaskets do not dump coolant into the crankcase, bad intake manifold gaskets do. You never should have pulled the heads for this problem.

 

Be sure your sending unit is properly grounded. Your gauge is powered and the sender provides the (variable) ground to provide the readings. If you ground the wire coming to the sender the gauge reads "Full". I suspect that your tank is at the back. If so, look for a disconnect in the cable ahead of that crossmember in front of the tank. You can do your diagnosing there first without disassembling anything. Eratic gauge action is often due to a poor ground.

 

I'll get under the van this week and ground the wire to see what happens. I have to get the wife unit to look at the gauge whilst I'm under there. She's still pissed at me for making her mix the concrete for the patio... but that's another story. You can't go wrong with a sturdy wife!

 

Just remind her that she'll be using the patio too. Also, make sure she understands that if this was 100 years ago; beside mixing the concrete, she would've had to pump the water up from a well before carrying it over in buckets to do the mixing. That should make her feel grateful and less angry with you.

 

The sad thing is that the dog decided to walk on it after we got all done troweling it smooth. I was out there past midnight making it look good again. The wife died laughing!

 

See everything worked out okay. Now it's just you, the dog, and the patio.

 

here in santa fe they pay extra for animal prints in their concrete..

 

I fixed my fuel indicator problem this past weekend. I had to drop the 36 gallon tank first. It had about 9 gallons in it so I got it part way down then siphoned the gas out. There are 3 straps holding it up there and the deep socket only fit on one of them. The others, I had to cut off the bolt end with a hacksaw cause it was way too long for the socket. Anyway I got it down, pulled off a few hoses and the 4 wire electrical plug and had access to the big unit in top of the tank. There is a big (8" or so) plastic ring which has to unscrew then the whole gas pump, filter and sending unit come out as one unit. I checked the sending unit on the bench with my trusty VTVM in the ohmmeter mode. It was open and every once in a while would make contact so it was bad. I was able to take it apart, find the washer looking thingy with crud on it, turn it around and make it work. Putting the tank back together was challenging in itself but I did get it all together and it worked great! So the bottom line is, the sending unit was bad!

Thank you all for your wonderful comments!