Bad Fuel Gauge

walktastic · May 13, 2008

Hi Im new to the forum and i just bought a 98 Sierra. Unfortunately, the gas needle has started to act strange. Ive heard of the fuel sending unit but ive also heard of using techron to clean out the sulfur in the tank. Has anybody tried this? if so, how many tanks did it take to clear out? The lady who i purchased the truck from hasnt driven it in almost 6 months. could this cause a major buildup too?

dbdave · May 13, 2008

I've had this happen to my Suburban several times but it mostly involved bad gas or corn gas on a long trip and the needle never came off empty. The Techron works to fix it, so does a fill of a 'Top Tier' gasoline. Since yours has been sitting for a while, it may take repeated treatments but I think it will recover.

walktastic · May 13, 2008

yeah ill just bite the bullet and fill up with 91 octane for awhile. i also forgot to mention that when i start it up the needle goes way past full. also when i have it in park it jumps back and forth. thanks for the replies.

jrrod2004 · May 13, 2008

maybe consider Seafoam in the tank a couple of times?

coachdubya · May 13, 2008

Walker,

Mine is doing this as well. Has for awhile. I'll give the Techron a shot and report back. (Once I get the damn thing started that is.)

ken1mod · May 13, 2008

Gentlemen,

You guys need to start using cheaper gas. I never have any problems and I use cheapest gas in town for 30 years. Really. And i get almost 19 mpg in my 5.3 in mixed driving.

Ken

coachdubya · May 13, 2008

That's all I've ever put in mine is pretty much is either RaceTrac or Sam's Club gas.

slimjim2525 · May 13, 2008

Gentlemen,

You guys need to start using cheaper gas. I never have any problems and I use cheapest gas in town for 30 years. Really. And i get almost 19 mpg in my 5.3 in mixed driving.

Ken

I agree, I use costco gas, last fill up was $3.55 a gallon. I've been driving my wifes car more lately until I get back to work.

AirForceAngler · May 13, 2008

An additional note also: Higher Octane does not equal better gas, either. Just that, higher octane. If you run higher octane that needed by your engine, you're wasting money also and maybe hurting your fuel economy.