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Fuel gauge reads 3/4 when tank full

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Old 04-08-2004, 06:57 PM
  #31  
AndyK
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So on the later cars, you cant clean the sending unit contacts by accessing the sender from the hatch (under carpeting)?? I'm confused.
Old 04-08-2004, 07:18 PM
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visualpascal
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From the picture in the tech session article, it looks like you should be able to clean the contacts on the unit itself...

--Chris
Old 04-08-2004, 07:23 PM
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Cyrus951
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Andy,

Pull out the rear carpeting, locate the sender, clean the terminals, and see if that did the job.
Old 04-10-2004, 02:44 PM
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z3bra
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Hmm well I tried this and with my tank as full as I can pump it my sender shows 3.4 Ohms across the terminals. (measured it at the gas station right after filling). Going by the paragon write up this should be more than the 3/4 tank mark but under the 4/4 tank mark. So lets say slightly under full since the resistance doesn't increase on a linear scale.

I cleaned the terminals up before measuring but they were pretty clean to begin with, so I'm thinking in this case I've probably got crud buildup inside the sender as some posts on this problem have suggested as a cause, and possibly a bad ground somewhere as well. I may just pull the gauge cluster anyway since I need to fix the reflectors since the silvering is beyond dead and if I have to tweak the needle a little that's fine, but I'd like to rule out the electrical problems first.

Anybody else had this double trouble?

Looking at the workshop manual wiring diagram, I see the ground is connected to the M II grounding point. The closest that the manual gets to telling you where this ground point actually exists is a dot somewhere near the fuse/relay box on an overhead view of the car. Does anybody know where this ground point actually is?
Old 04-10-2004, 02:48 PM
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GOBOGIE
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Default Re: Fuel gauge reads 3/4 when tank full

Originally posted by fokker
"You gay Fokker?"... Meet The Parents


Sorry couldn't resist!
Old 04-10-2004, 03:43 PM
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Default Re: Re: Fuel gauge reads 3/4 when tank full

Originally posted by GOBOGIE
"You gay Fokker?"... Meet The Parents


Sorry couldn't resist!
Great movie!
Old 12-29-2004, 04:52 PM
  #37  
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Here's a follow-up note to an old thread.
I resoldered the spade connectors on the fuel level sender and that seemed to help in addition to cleaning the terminals with a wire brush. The resistance between the grounding bolt and the ground terminal on the fuel level sender dropped from 0.5 ohm to 0 ohms.



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