Zuti
fuel gauge question
Le Mans Master
Joined: May 2006
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From: Pittsburgh suburbs Pa.
Burning Brakes
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From: Sullivan Illinois
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Techron 
Burning Brakes
Joined: Aug 2011
Posts: 1,160
Likes: 113
From: Vancouver Island
my fuel gauge was acting strange too, i used GM's fuel system cleaner. they have two, i used the stronger more expensive one. seemed to work real good, haven't had any problems since. i would have used techron but we can't get it anymore up here in Canada. if you do a search there is a number of issue's that can happen with the fuel senders and the jet siphon pump. good luck 
Pro
Joined: Sep 2013
Posts: 538
Likes: 6
From: Knoxville TN
St. Jude Donor '14
I had the exact same issue about 2 months ago. I ran two bottles of Techron through the system. Everything seems to be working pretty good now. It's definitely a cheaper alternative than replacing the fuel sensors.
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You could replace the fuel level sensors in both tanks since that is what the problem is. ie corrosion buildup on the sensors. Techron (large bottle) added to a less than half full tank of fuel and then fill the tank usually solves the problem a lot less expensively than new sensors. Sometimes it takes a few retreats to get the sensors cleaned up and then once a year when you change the oil add another large bottle of Techron to a less than half full tank of fuel and fill it up.
Try the Techron first.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
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From: Columbia SC
If you end up deciding to replace the senders make sure you get the later model AC Delco MU 1218 (updated P/N from MU1004) for the passenger side. it uses 3 wires and not 4 like the 97-98 did. Don't remember if the driver side changed, not at home now. Let us know how things go.
I worked with a guy in Germany a long time back who kept ordering the wrong right side sender (vendor said it SHOULD work) for his earlier car and just couldn't figure out how to make things work until we FINALLY had him order the CORRECT sender.
I worked with a guy in Germany a long time back who kept ordering the wrong right side sender (vendor said it SHOULD work) for his earlier car and just couldn't figure out how to make things work until we FINALLY had him order the CORRECT sender.
Intermediate
Joined: Mar 2013
Posts: 30
Likes: 0
From: Reading PA
I've had the fuel gauge problem 4 times on my 1999 coupe. Mine would usually read half full after I filled up then slowly creep up to full. Techron solved the problem 3 times. On one occasion my fuel gauge read empty on a full tank and wouldn't budge. I tried the Techron again and nothing happened. I tried a second time at the next fill up and still nothing. I then went into the codes and had a fuel code (can't remember exactly which one), I reset it and the fuel gauge worked properly again.
Melting Slicks
Joined: Mar 2004
Posts: 2,396
Likes: 407
From: Horseshoe Bend ID
Pull the codes from the DIC. This will help diagnose the problem. Look for these:
DTC P0461 Fuel Level Sensor Performance
DTC P0462 Fuel Level Sensor Circuit Low Voltage
DTC P0463 Fuel Level Sensor Circuit High Voltage
DTC P1431 Fuel Level Sensor 2 Performance
DTC P1432 Fuel Level Sensor 2 Circuit Low Voltage
DTC P1433 Fuel Level Sensor 2 Circuit High Voltage
DTC P0461 Fuel Level Sensor Performance
DTC P0462 Fuel Level Sensor Circuit Low Voltage
DTC P0463 Fuel Level Sensor Circuit High Voltage
DTC P1431 Fuel Level Sensor 2 Performance
DTC P1432 Fuel Level Sensor 2 Circuit Low Voltage
DTC P1433 Fuel Level Sensor 2 Circuit High Voltage
Racer
Joined: Nov 2006
Posts: 297
Likes: 26
From: San Jose California
Techron is in Chevron and Texaco gas
If you're near a Chevron or Texaco (same gas) station, start using their gas for a few tanks. I always use Chevron because it has Techron already in it. If you are having fuel level problems, you might need to use a few bottles of concentrate to clean up the existing Sulphur deposits, but just using Chevron or Texaco on a regular basis will keep your fuel sensors clean without the need to add extra Techron.
Racer
Joined: Jul 2006
Posts: 444
Likes: 56
From: DeBary Florida
Like everyone else here "TECHRON" is the way to go. Also make sure to use a Top Tier Fuel like, guess what? Chevron with "TECHRON".
http://www.toptiergas.com/
http://www.toptiergas.com/