I’ve never been a big fan of various “additives” for fluids in the car. Most of them are pure “snake oil” in the metaphorical sense–the “cleaning” job they do is cleaning your wallet of any unwanted cash…and wanted cash as well.
Let me give a little background. The grocery store I use most of the time provides “points” which can be worth a discount for fuel. To get the most benefit from that, I tend to run the car to nearly empty then fill it up. With a 22 1/2 gallon tank, if I run it down to the last couple of gallons each $0.10 per gallon off is worth a couple of bucks. It adds up over time.
However, that requires that I have a truly reliable fuel gauge. Now, a while back it started getting squirrelly. Specifically, it would sometimes just drop to zero even though I had plenty of gas in the tank. Now, this isn’t earthshaking. I could use the odometer and a knowledge of how far I can get on a full tank . But that depends on how what kind of driving I was doing. More highway, less stop-and-go in traffic. Carrying heavy loads or not. That sort of thing can effect how far I can get on a tank of gas. Which means I would need to leave more margin…which means I wouldn’t get all the benefit form the “cents off” that I could if I had a more reliable measure of remaining fuel.
It got to the point where I was considering replacing the fuel gauge sending unit (having eliminated other parts of the system as likely sources of the problem. It wouldn’t be worth it to take it to the shop, but as a DIY project, the cost/benefit ratio looked good. Researching it I found that it would be a pretty big project, and something I’d have to rope friends into since it did not look like a reasonable one-person job.
As it happened, while researching the procedure for dropping the tank to get access to the fuel pump/fuel gauge sending unit, I came across a video where someone described the very problem I was having and said that the cause was the “high sulfur” fuel in his area which gunked up the sending unit causing it to fail. The “fix” was to run a couple of tanks worth with a detergent fuel additive, specifically Chevron concentrate with Techron.
I thought…”Worth a try.” So I bought a couple of bottles (12 oz size at local store–the above link is for the 20 oz size). Two bottles of the 12 oz size or one 20 oz were appropriate for the size tank in my car. I added them and filled the tank, ran it low, added two more and filled the tank and…
My gauge started working properly again.
I was seriously, seriously skeptical when I first tried it. Like I said, most such products are snake oil. However, for this particular application, this particular product does seem to work.
Saved me a wasted afternoon and a chunk of change swapping out the fuel pump and sending unit.