I've started getting some very erratic fuel gauge readings on my 96 ram 5.9 Some history. About 3 weeks ago pulling boat up grades I got a check engine light. Replaced O2 sensor and all seems well. Truck appears to be running ok. At the time of the O2 issue I noticed my fuel gauge was reading strange especially when the truck was under load. Even if I had more than 1/2 a tank the guage would drop to near empty and once the load was off the motor the guage would migrate back up. Anyways, the guage would read near empty. Go to fill up and only took 10 gals.

I'm wondering if anyone has any ideas? I'm thinking the sending unit/fuel pump assy might be going out. If this is the case is it difficult to replace? I know you have to drop the tank but just wondering if this is best left to a shop or can it be done over the course of a weekend?

Thanks, mark

 

an old post with info on the gas gauge fix.
Consider trying the relatively cheap 'Techron Concentrate Plus' cleaning first.
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fuel gauge sender fix

https://dodgeforum.com/m_675391/tm.htm

sulfur in gasoline poisoning Chrysler style sender resistance strip:
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Chrysler fuel senders that are inside the fuel tank use a silver alloy on the strip that the float's slider rubs against to vary the electrical resistance that works the gas gauge.

Sulfur in gasoline (or diesel) can foul or 'poison' this Chrysler part much easier than GM or Ford's sender.

You can read about this sulfur killing DCX fuel gauges at these weblinks:

http://web.archive.org/web/200206110...er/3378552.htm

http://www.whnet.com/4x4/bad_fuel.txt

As others have said, you may be stuck having to replace the fuel unit.

On Diesel Truck Resource and Turbo Diesel Register some Ram owners have reported that they have been able to clean and fix the resistor slider - but only after pulling it from the tank.

It is only 50/50 chance
but you might be able to get the fuel gauge working again by using a heavy concentration
of a cleaner like Chevron Techron, Napa's "Kleen" or a few cans of official Mopar Fuel Injection cleaner from the Dodge dealership. Whether to spend $18-36 in a gamble to see if it would avoid buying a new in-tank unit is up to you.

Over on another forum (Moparts) there is a long time poster who goes by Mr P Body who claims he was in charge of testing many fuel injector cleaners in order to choose the official one Mopar uses, which he claims works significantly better.

The newer version of Chevron's cleaner (Techron Concentrated Plus) mentions improving fuel sender operation after sulfur fouling.
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also check out this old post

https://dodgeforum.com/m_508851/tm.htm

 

Thanks. If I was to try the fuel cleaner first how many cans should I intially put in?

Mark