Ok so I was dicking around with my fuel gage on my 69 442 because it is Pegging out past full when the key is on. I have no idea what is wrong with it. Any help would be great. Either what to try or where to buy another one.

 

NEVER mind just searches and seems a few people have this same problem. I am gonna try there suggestions first sorry.

 

A gauge going past full when the key is on means an open circuit (infinite resistance). The easiest thing to check is to make sure the ground wire coming off the fuel tank sending unit is connected and not corroded. This will be under the car forward of the tank. You'll likely have to put the rear of the car on jack stands to be able to get under there with enough room to work if you do find this to be the problem.

If the ground checks out ok, the next thing is to check the other wire coming off the sending unit and running all the way to the gauge. This wire likely comes rearward and connects to the wire coming from the gauge in the area near the license plate. But wherever it is, you need to trace this wire and make sure there are no breaks in it.

When you find this wire, find the place where the wire coming from the tank connects to the wire coming from gauge. There will likely be a plastic connector that snaps the two wires together. Pull this apart, ground the side coming from the gauge, and turn the key on. The gauge should immediately peg on "E." If it does, then you know there is no problem with the gauge itself.

If the gauge checks out ok and you don't find a break in the wire, then you probably need a new sending unit. I don't know if that requires dropping the tank on your car or if it can be removed and replaced with the tank in place.

 

I'd just take it as another silly old car thing and not worry about it. Mine does it too.

 

Sounds like a great way to run into a problem and out of gas!!!!

Its a simple problem to diagnose and fix. Don't ignore it because it won't go away on its own.

 

Fuel sending unit bad or ground wiring bad on the fuel sender?

You can take out the sender and do an OHM test on it.

 

You do have to drop the tank to replace the sending unit as it is on top. If the sending unit is bad, you can have it rebuilt (Year One did the one on my '68 4-4-2 and the results were great). As well, Fusick makes a replacement tank sending unit (2 line, part number FTU680-2, see www.Fusick.com and their on-line catalog) for about $90 plus shipping.

Randy C.

 

$31 online for a fuel sending unit replacement.

http://www.google.com/products/catal...ed=0CFYQ8wIwAw

Plenty of other places online for $48-$50.

 

On mine, it goes back down to the actual tank level once you start the car. No problems/gas shortages in 3 years of daily driving.

 

...he said as he rolled to a stop in the middle of nowhere.

 

I bought the Old $39.00 Special..
I will gurantee that is my problem..
One size fits all doesnt work..
Tomorrow I call Mr. Steve O'Brien at Fusick..

 

Thanks guys I will try all this tomorrow morning.

 

Ok grounded the wire and gauge went to e so ill drop the tank while she only has a gallon or two left and ohm check the sending unit. It should go from 0 to 90 right?

 

Yes, the sending unit resistance should vary between 0 and 90.

It's at least something that you know that the gauge itself seems to be ok.

If you're going to go through the bother of dropping the tank, which is never a fun thing to do even under the best of circumstances, you ought to put a new sending unit in regardless of the condition of the old one. Rockauto.com has them new for your car for only about $40. That's not much in the grand scheme of things.

The fact that your gauge pegs past full when connected still suggests to me the possibility of an open in the circuit somewhere. Maybe when you get the tank down you'll discover that there's a problem where the wire from the gauge connects to the top of the tank. Maybe you won't have to open the tank at all.

But you still have to lower the tank to do even this, and, if you've done that, getting the old sending unit out is simple, so even if it turns out to be just a loose wire, your sending unit is still 42 years old, so you might as well put in a new one.

Remember, the only thing worse than having to lower the tank once is having to lower the tank twice!

 

There seems to be a conspiracy directed against 1970 Delta 88's. I don't find an oe replacement from RockAuto or Fusick. Apparently I am going to be forced to work on the beast myself, save money, and gain honor.

 

One from a different year might work. I needed one for my '67 Delta 88, and those aren't made, either. But one for a '72 Buick LeSabre (which I think is the same as for a '72 Delta 88, but I've never compared part numbers), is a drop-in replacement, and rockauto does have those. I got mine for about $70. I wouldn't be surprised if the same thing fits in your car's tank. What matters is the size of the opening that it screws into as well as how far down into the tank the fuel pickup line and float extend. If you have no other way of checking, you could order the rockauto unit and then compare it side-by-side with yours, and if they're a match dimension-wise, you're good to go. If not, return the unit to rockauto.

In my experience, Fusick, which has the reputation of being a wonderful source for Oldsmobile parts, often comes up short on things like this for the big cars. All you have to do is compare the sizes of their two catalogs. Their Cutlass catalog is about 100 pages. Their big-car catalog ('61 to '75) is about 40 pages. I'm not saying they don't sell good stuff. Whatever I've bought from them has been top notch. But there are a lot of things they don't have.