eratic fuel gauge >> help

[boatbuster]

Just traded up to my 3rd Astro, I just love these vans. This one has the fuel gauge working great for a couple of days and all of a sudden it drops down to empty and the low fuel light comes on. Then when it feels like it, it comes back to where it should be. I was thinking of a bad ground, but I don't know where to start looking. Any body have a wiring diagram for this van or any ideas as to how to fix this problem. Thanks!

[Blue Bowtie]

If you are fortunate, it will only be a ground. I've had two of these recently, and both were the sending unit, however (including my wife's Astro). If you determine that's the problem, you'll get to drop the fuel tank to repair it:



Pull the tank unit:



Remove the level sensor:



...And repair the sensor. The bifurcated wiper contacts on the resistor assembly lose their tension, and the pivot works loose. The two factors combined is enough to cause an intermittent loss of contact and drop the gauge to ZERO.



While the tank unit is out, it would be a good idea to check the pump and sensor connectors in the op of the tank. They tend to overheat, and can be replaced with an upgraded aftermarket harness assembly.

[boatbuster]

WOW!!! Now that's details!!! Thanks for the pictures and step by step intsructions!!!

[drew300]

I don't know if it will help, but I had a loose ground a couple of inches ahead of the tank. It's a post welded to the frame, and the nut, (my my case), was loose and corroded.

[Blue Bowtie]

Drew makes an excellent point - Don't overlook the simple things first. The ground he mentioned, AND the harness connector in the same vicinity should be checked before you even consider dropping the tank. You may be fortunate. I have not been lately.

[speedbump49]

Hey BB, You Rock! I am looking at my own fuel pump wire socket and its burnt too just like your picture (or a little worst). Your post mentioned upgrading to an aftermarket wiring harness, where might I find that?
Also, do you think its just shit wiring or could the overheating of this wire mean a more serious problem indicating I should replace the fuel pump anyway?

I value your opinion. Thanks again.
Cheers,
-mw

[2001 ASTRO DUDE]

Originally Posted by speedbump49

Hey BB, You Rock! I am looking at my own fuel pump wire socket and its burnt too just like your picture (or a little worst). Your post mentioned upgrading to an aftermarket wiring harness, where might I find that?
Also, do you think its just shit wiring or could the overheating of this wire mean a more serious problem indicating I should replace the fuel pump anyway?

I value your opinion. Thanks again.
Cheers,
-mw

I replaced my fuel pump assembly (included the sending unit also) just this weekend. I have had some erratic fuel gauge readings in the past also. I called Advance Auto Parts and they recommended replacing the wiring harness that is part of the fuel pump assembly. They did not have the pump in stock but did have the wiring harness. I got the pump assembly from Autozone and it was complete with the new wiring harness pre-installed. Now I have a wiring harness that I have to return to the store. It seems to me that by the computer system at Advance recommending replacement, that this may be a common problem. Just my $0.02.