Fuel Gauge Problem???

**peterlawl84** · 04-03-2009, 07:18 PM

About a month ago I noticed my fuel gauge stays on full for the first ~150 miles and then slowly begins to drop, but never to the right place. I tried to search, but I guess I have not figured out how to use the new search.
Anyone know if its an easy fix or what I need to do?

**0rion** · 04-03-2009, 09:10 PM

could be a bad sending unit although these cars are known to have fuel gauge issues. You could try ohming it out back at the tank and verifying if the ohms from the tank match what the gauge is reading. The 2 purple wires are the ones you want to ohm out and the ohms are 40 (empty) to 259 (full).

**peterlawl84** · 04-04-2009, 10:45 AM

How do I access the sending unit? Do I have to jack the car up?

**bigrondownhiller** · 04-04-2009, 02:27 PM

My car has been doing the same thing for a couple of years. I am pretty sure it is the sending unit but dropping the tank to change it is a lot of work. I have it figured out that when the guage reads 1/2 a tank there is actually closer to 1/4.

**chuckie669** · 04-04-2009, 02:31 PM

Originally Posted by bigrondownhiller

My car has been doing the same thing for a couple of years. I am pretty sure it is the sending unit but dropping the tank to change it is a lot of work. I have it figured out that when the guage reads 1/2 a tank there is actually closer to 1/4.

+1. Mines had same issue as yours for a few years. Under 1/2 tank can get goofy on the gauges. Over that never had a problem. I'm not dropping the tank for that shit.

**pajeff02** · 04-04-2009, 03:08 PM

For what it is worth -- the sulfer in the fuel (if I recall correctly) can cause problems with fuel guage senders. Chevron Techron Fuel System Cleaner is supposed to rectify this issue. I am not one to fall for advertising hype but Hemmings Muscle Machines had an article last year and I believe this is the fuel system cleaner that was recommended.

**peterlawl84** · 04-05-2009, 05:20 PM

my problem is not under 1/2 tank, its from full to who knows....it just stays on full, even though I know there is only like ~1/4 tank (seems like the problem is getting worse)

**0rion** · 04-05-2009, 06:11 PM

Originally Posted by peterlawl84

How do I access the sending unit? Do I have to jack the car up?

yes, back at the rear axle you'll see the harness that goes into the fuel tank. Look for the 2 purple wires on that harness and set your multimeter on ohms and ohm across those 2 purple wires. It would help if you have a rough idea how much gas is in there so you'd know what you're looking at. If you know it's well below full or even less than half and it's still ohming out at almost full then I'd say your sending until could possibly be the culprit.

**gnomee** · 04-05-2009, 07:25 PM

Originally Posted by pajeff02

For what it is worth -- the sulfer in the fuel (if I recall correctly) can cause problems with fuel guage senders. Chevron Techron Fuel System Cleaner is supposed to rectify this issue. I am not one to fall for advertising hype but Hemmings Muscle Machines had an article last year and I believe this is the fuel system cleaner that was recommended.

+1 for the type of gas.

If you regularly by gas anywhere anytime the inconsistency seems to cause extra problems. I had a similar problem after a long road trip. After two tanks at our local chain QuikTrip and my guage was back to working great. Their gas has a cleaning agent like the Chevron gas.

I think most of the bigger chains all have something but the little guys generally do not.

The sending units in these cars have problems, but you might get lucky switching to a higher quality fuel.

**peterlawl84** · 04-05-2009, 08:54 PM

I only fill up at quiktrip or the sam's club (mostly quiktrip) and use premium since it was tuned about 4 yrs ago. I will check the ohms across the sending unit as soon as I can. Is that something easy to replace? I wish I knew about that 2 wks ago when we had the car up to replace the torque arm (dang! oh well!)