Liquid fix for my fuel sending unit

[V8Bubble]

Howdy all.

For years my fuel gauge always read correctly, and then a few years back it started to act up like reading 1/2 on a full tank and making big jumps on the gauge with minor changes in the fuel level or the sloshing of fuel while driving. I was hoping it was just a lack of use causing the contact points on the sending unit to not register correctly. When I replaced my dented (from a previous owner) fuel tank I checked the sending unit with an ohm meter and the ends of the range were correct, but the sweep in between was spotty. I was still hopeful that just driving the car more would wear it back in, and often new replacement parts aren't that great these days. After everything was back together and I was able to drive the car more nothing improved with the fuel level reading. Soon after I ran across a discussion about how sulphur in modern fuels can build up on sending units and cause bad readings. Based on some success stories in that discussion I tried a bottle of Techron Complete Fuel System Cleaner. Poured the whole bottle in the tank and then over the next few days I'd occasionally bounce the back of the car to slosh it around. Within a week the fuel gauge was reading correctly again and has been fine ever since. It was a big relief knowing I wouldn't have to pull the tank that I had just installed.

Sharing this info in case someone else runs in to the same issue.

Take care,
Mike

[bob85gt]

thanks, mine stop going to full a year or so ago. i will give it a try.

[Drivunn]

All the corvette guys swear by Techron cause their senders coat up sitting around with no miles on them. Dropping tanks to change senders $1500 and as often as every 35000 miles - about 10 years in Corvette time! . Our 2007 Ram 1500 wouldn’t register tank level and so I tried couple of tanks with Techron but was unsuccessful. Dealer said I needed a new instrument panel for $1600. Back to more Techron. Gauge has been working correctly for 2 years! Good stuff now part of maintenance schedule. You can just buy Chevron gas with Techron as well.

[85stanggt]

Thank you so much for this suggestion! I just started having this problem recently, which corresponds with me not driving the car much these days any more. If this could solve the issue -- wow! would that make life easier.

[richpet]

I have always had great luck and results with SeaFoam. For example:
The 1500cc Goldwing motorcycles (1987-2000) used a dual carb setup that had super small passages. The carb enabled it to get awesome economy, decent power, etc. But if you let them sit (especially with ethanol blend fuel) they had a tendency to clog a bit. Many who did not ride them often enough had to pull the carbs and rebuild. NOT a pleasant task or for the faint of heart.
I had a 2000 model that had sat for two full years when I bought it in 2005 with barely 10k on the odo. It idled a tad rough. In went SeaFoam and a full tank of fuel. Rode it a bit aggressively, let it idle for a while, repeatedly throughout the tank. Problem gone. I did a SeaFoam tank once a year and the bike ran flawlessly, returning 37-42 MPG (not bad for a 1000 lb touring bike) throughout the remainder of its life. That life sadly ended in 2016 when I got rear ended, totaling the bike. The odo showed 130k+ and was still purring like a kitten and smooth as silk.