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Hey guys, have seen this posted but have a question. My Gas Gauge pins to E after I fill and use about 1/4-1/2 a tank. Ive used Techron and I use Sunoco Premium fuel, and its still doing it. The repair shop I use cant get a replacement sensor (all backorder) my question is, if i just use the Trip gauge to monitor my mile after the gauge pins to E- even though I have fuel in the tanks, will the vehicle run out of gas or stall as it isnt reading any fuel? Sorry if this has been address in the past, I cant find anything regarding just using the Trip gauge to monitor fuel usage. Thank for you guidence
Patience is key! It took me over 1,200 miles, and at least 4 or 5 bottles of Techron before mine worked right. No guarantee this will work for you, but I think it works for the majority of us.....
I lost all patience. Over 3,000 miles and 12 bottles of Techron. Obviously Techron is not the solution. I think it is foolish to believe Techron would really work. Anything that needs to be cleaned has to be scrubbed. Pouring a solvent on something doesn't cleaned it. You have to scrub it. The Techron actually working is just in everybody's mind.
Thanks all for your help. I will continue to monitor and just fill it up when the needle pins to E around 1/2-3/4, ill use the Trip sensor to monitor.. Hopefully it will begin to work after another Techron try
Thanks all for your help. I will continue to monitor and just fill it up when the needle pins to E around 1/2-3/4, ill use the Trip sensor to monitor.. Hopefully it will begin to work after another Techron try
My car was acting very much like yours when I bought it 4 years ago. If I recall correctly the low fuel light appeared to correspond to the gauge, such that even with full tank if my gauge was reading at or near empty the light went on. But I may not be recalling correctly.
What I do recall is that it took several treatments of Techron before the gauge started acting right. You want to add the Techron when your fuel level is as low as possible, this will ensure that the Techron gets into both of the tanks. So don't give up on the Techron. This is a very common issue with the fuel sensors and many on this forum can vouch for the fact that Techron can solve this sort of issue.
When I say several treatments, in the case of my car, I think I might have used 4 or 5 bottles in the first year of ownership. Thereafter a couple of more the second year; and I still have a bottle of Techron in my trunk that I haven't had to use in over two years. You are on the right track to use the top tier gasoline- I run my car almost exclusively on Costco's premium.
Thanks so much.. just frustrating.. in any case will continue to try to solve it with Techron.. Its not an everyda driver, so it takes a while to run the fuel level down, and with an intermitnet gauge i wanted to make sure that i wouldnt run out of fuel..
Yes, this issue is very frustrating and I was certain my gauge was broken and this was something I would simply have to live with or pay to have the sensors replaced. But my car is proof that the repeated treatment with Techron can be a cheap and so far a permanent fix.
I've always been skeptical of any kind of fuel additives as "snake oil" but Techron can actually work to clean the sensors and restore the gauge. The Corvette wasn't the only car using silver in their fuel sensors and apparently it is the gasolines with the higher sulphur content, or those gasolines lacking the additives to combat the effects of sulphur that caused the issues with these sensors. You might consider daily driving your Corvette for awhile and driving it until you are low on fuel (maybe keep a couple of gallons in a gas can in your trunk, just in case)- then adding in the Techron with each fill up. My gauge started working more often than not at first, then eventually the problem went away entirely. I do suspect, the cars when left to sit are more prone to developing this issue.
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Techron may require two or more treatments to do the job. It has been shown to remove the sulfur deposits from the fuel sending unit, but in some cases replacement of the sending units may be required. I would go ahead and try some more Techron though before looking at buying parts.
Top-tier gas and Techron has largely eliminated this problem on my '99. When it did happen, it was when the tank was between 1/2 and 2/3 full and I had been driving for about one hour. If I stopped and turned the ignition off and then back on, it would go back to normal. If I kept driving it would flip back on when the fuel level got down to about 1/3 full.
Mine has been doing this off and on recently and finally quit. I am on my second tank of Techron on an empy tank so I am hoping this cures it. I replaced the Left tank pump/pickup/sending unit assembly last May with a brand new AC Delco Unit. I then replaced the right unit with a low mileage OEM part. It worked fine for a year and now its doing it again. Hitting the reset button gives me a half tank reading on a full tank while the car isn't running, then goes to zero once I start it.
My codes are:
PO461 Fuel Level Sensor 1 Circuit Perfomrance
PO463 Fuel Level Sensor 1 Current High Voltage
I have a similar problem. When I fill up the tank, my needle pins to "empty". After I burn off about 5 or 6 gallons, the gauge starts working again. No amount of additives will help with my problem, as I have replaced the fuel pump three times with brand new (extremely expensive) fuel pumps. All came with the new sending unit/float included. After the third unit, it was obvious that neither the pump, or the sending unit was the culprit. Still trying to diagnose the problem.
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Originally Posted by aahrested
I have a similar problem. When I fill up the tank, my needle pins to "empty". After I burn off about 5 or 6 gallons, the gauge starts working again. No amount of additives will help with my problem, as I have replaced the fuel pump three times with brand new (extremely expensive) fuel pumps. All came with the new sending unit/float included. After the third unit, it was obvious that neither the pump, or the sending unit was the culprit. Still trying to diagnose the problem.
Correct, this article from the C5 Registry explains how the dual tank system works.
The C5 Corvette has two fuel tanks, left and right hand. The left hand tank contains the electric fuel pump that supplies fuel to the engine. The right hand tank has a pump, which transfers fuel from the right tank to the left tank. The pump in the right hand tank has no moving parts and is not really a pump. It is a siphon device that uses fuel pressure from the left hand pump to start a siphon that transfers fuel from the right hand tank to the left hand tank. In order to create this siphon, the fuel line that goes to the engine splits and a small amount of pressure is routed to the right hand tank to start the siphoning. The fuel that is being siphoned is routed through another hose to the left hand tank. If the left hand tank is full, the fuel transfers back to the right hand tank through the large filler tube located at the top of the tanks.
The idea is to always keep the left hand tank full whenever there is fuel in the right hand tank. When the fuel gauge reaches a half tank, the right hand tank is empty and the left hand tank is full. Both tanks have a float and sender that measures the fuel level in the tank. These signals go to the Powertrain Control Module (PCM) which interprets the information and sends a signal to the Body Control Module (BCM) which then sends a signal to the fuel gauge in the Instrument Cluster.
Because of the variation in tanks and sending units, the PCM doesn't always read the actual fuel level in the tank. Above or below preset voltage limits, the fuel level is estimated. The voltage limits for each sending unit, right and left, are set to represent "full" and "empty." When one or both tanks have exceeded the preset limits, either "full" or "empty," the system is estimating the actual fuel level. This happens when both tanks are full, gauge is "full;" when the right tank is empty and the left tank is full, "half" on the gauge, or when both tanks are empty, gauge is at "empty."
This estimating strategy and the physical layout of the system results in an unusual fuel gauge characteristic that may be noticeable to some people. When the fuel level is at or near half tank, the right hand tank is empty and the left hand tank is full, so the system is estimating the actual fuel level. Because of the siphoning system, when the car sets without running, the fuel level equalizes in the two tanks. When the car is first started, the system is actually reading the fuel level in both the right and left hand tanks. After running for several minutes, the fuel in the right hand tank has been transferred to the left hand tank, leaving the right hand tank empty and the left hand tank full. The change in the fuel levels results in the system changing from reading the actual fuel level to estimating the fuel level. This change results in the fuel gauge reading actually indicating more fuel than when the car was first started.
One of the common concerns with the Corvette is the fuel gauge goes to "empty" intermittently. First, let's discuss why this happens. As previously mentioned, the system estimates the fuel level at certain times. When the signal from the left hand sender is above the preset voltage limit, the system estimates the left hand tank fuel level to be full. When the signal from the right hand sender is below the preset voltage limit, the computer estimates the right hand tank fuel level to be empty.
In this situation, left tank full and right tank empty, the computer estimates the fuel level and sets that gauge at half tank. Once the fuel level in the left hand tank goes below the preset voltage limit, less than full, the computer begins reading the actual fuel level and setting the gauge accordingly. At this time the computer expects to see the voltage signal from the right hand tank stay below the preset limit that indicates empty. The problem comes from the fact that the signal from the right hand tank does not stay below the preset limit. When the computer sees the right hand signal voltage exceed the preset empty limit, it assumes that there is a problem in the fuel transfer system, which is a possibility. When this condition exists, the computer software turns on the Check Gauges light and commands the fuel gauge to the empty position. The logic for this is, if there were a problem with the fuel transfer system and fuel was not being transferred from the right hand tank into the left hand tank, you could have the gauge indicate half tank, when then the left hand tank would be empty and the right hand tank would be full. In this situation you would run out of gas and be walking.
On some Corvettes the situation that is occurring now is the result of the right hand sending unit being attacked by compounds within reformulated gasoline. This condition manifests itself as an erratic voltage signal from the right hand sending unit. In the above scenario, left tank full and right tank empty, gauge at half, the computer looks for the voltage signal from the right hand tank to stay below a preset level. The erratic voltage signal caused by the reformulated gasoline causes the computer to think there is fuel in the right hand tank when there is not. When this happens the computer software turns on the Check Gauges light and commands the fuel gauge to empty. GM has issued a revised computer software, for 1999 through early 2002 models, that raises the right hand preset voltage empty limit to prevent the erratic voltage signal from causing this situation. While it has proven to be an effective solution, it has not corrected the concern in all instances.
Another possible resolution is to use Techron fuel system cleaner. This has also worked in many, but not all cases.
Thanks so much.. just frustrating.. in any case will continue to try to solve it with Techron.. Its not an everyda driver, so it takes a while to run the fuel level down, and with an intermitnet gauge i wanted to make sure that i wouldnt run out of fuel..
Patience is key! It took me over 1,200 miles, and at least 4 or 5 bottles of Techron before mine worked right. No guarantee this will work for you, but I think it works for the majority of us.....
Came here to ask this same question. This just happened to me for the 1st time today, but I've only the car for 3 weeks.
Leaving the grocery store, and had just a hair under 1/2 tank. Got about 6-7 miles away, and noticed the "Check Gages" light.
So, what's the consensus? Techron or Seafoam? I've used Seafoam for years, but haven't put any in this car yet.
I do use top tier fuel, premium. I live in a rural area, but it just so happens that the only local gas station is a Citgo.
Below is a great video from Project Farm comparing Techron to Seafoam. Both are good products and have worked for me to remedy the C5 gas gauge issue (remedy...not solve, as the issue still comes abd goes. Just not consistent anymore) .
Seafoam also solved a misfire issue in my old 2005 F150. Truck would stumble in OD over 75mph. Seafoam solved the issue.
C5 Fuel Gauge Sensor issue
