P0461 code - fuel gauge reads empty
10-14-2015, 11:42 AM
#1
Racer
Thread Starter
P0461 code - fuel gauge reads empty
So I bought a 2009 Corvette a month ago or so. It's a base LS3 with the Z51 package in a manual.
On my way home from buying it, I stopped and filled the tank up completely. As soon as I turned on the car, I got a code (P2068 - Fuel level sensor B circuit high) and it said "Service Fuel System" also "Low Fuel". The gauge read empty. Well I continued to drive it home and eventually after some miles, the gauge started working again.
I filled it up again the next day and the same thing happened. After doing some research, I discovered it was likely the sender in the passenger side tank. I had some mods planned already and swapping in a Z06 pump was one of them. So we were already planning to drop the tank. I had my local GM performance shop (who works on C6s every day, there's always at least half dozen there, different ones though) order me a new Z06 pump assembly with a sender and a new sender for the passenger side tank. They dropped the tanks and replaced the pump and senders. At the same time we added some 85# injectors, some headers, and a flex fuel sensor.
All looked good, the tank had a couple gallons of 93 in it, we threw it on the dyno, tuned it for 93 and all was good (she made around 415 hp/420 tq SAE if I remember right on the DynoJet). Now came time to put in some e85 (which tested 86%), so we commanded on the pump to get the 93 out, and as it was pumping out, the gauge was going UP! It stopped around half a tank when the tank was empty. So we dumped in 10 gallons of e85 and the gauge started to go down until it ready empty. And then we did a quick tune (made about 425/425 I think). We planned to tune it more in depth later as we were short on time that day as it was almost 5:30 already.
So the gauge was obviously having issues still. We thought maybe the tanks were not equalized or something, so I drove it home and stopped for some more e85 and put another 8 gallons or so in it (whatever it took to fill it). Still read empty, and now I scanned it and there was a P0461 code - Fuel level sensor circuit range/performance.
The next day they dropped the tanks again and took it all apart, they tested the senders separately off the car and the range on the Ohmmeter was correct 44-250 or something. They even swapped my old sender from the driver side back in. No luck, same code. We double checked the part numbers to make sure the senders were for the 08+ (or 07+?) for when they reversed the Ohm readings and they were correct. So now I have it back as I am driving the car to Florida for vacation, I guess I will be using the trip odometer a lot. They ordered a second set of senders again and will try again next week to swap them and see what happens. Also they are going to try and read some info from the BCM and ECU with something like a tech-2 (or whatever the latest version is called now). Oh and if I clear the code, the gauge goes to about half a tank and them 30 seconds later it goes back to empty and the code is back.
Anyone every had similar issues? I did a ton of searching and didn't come up with much that was helpful. The shop is doing their own research this week as well.
Sorry for the long post, and thanks in advance!
TL;DR - Car has P0461 code and gauge reads empty, replaced both senders already, no luck. Going to try and replace a 2nd time. Looking for any ideas.
-Jesse
On my way home from buying it, I stopped and filled the tank up completely. As soon as I turned on the car, I got a code (P2068 - Fuel level sensor B circuit high) and it said "Service Fuel System" also "Low Fuel". The gauge read empty. Well I continued to drive it home and eventually after some miles, the gauge started working again.
I filled it up again the next day and the same thing happened. After doing some research, I discovered it was likely the sender in the passenger side tank. I had some mods planned already and swapping in a Z06 pump was one of them. So we were already planning to drop the tank. I had my local GM performance shop (who works on C6s every day, there's always at least half dozen there, different ones though) order me a new Z06 pump assembly with a sender and a new sender for the passenger side tank. They dropped the tanks and replaced the pump and senders. At the same time we added some 85# injectors, some headers, and a flex fuel sensor.
All looked good, the tank had a couple gallons of 93 in it, we threw it on the dyno, tuned it for 93 and all was good (she made around 415 hp/420 tq SAE if I remember right on the DynoJet). Now came time to put in some e85 (which tested 86%), so we commanded on the pump to get the 93 out, and as it was pumping out, the gauge was going UP! It stopped around half a tank when the tank was empty. So we dumped in 10 gallons of e85 and the gauge started to go down until it ready empty. And then we did a quick tune (made about 425/425 I think). We planned to tune it more in depth later as we were short on time that day as it was almost 5:30 already.
So the gauge was obviously having issues still. We thought maybe the tanks were not equalized or something, so I drove it home and stopped for some more e85 and put another 8 gallons or so in it (whatever it took to fill it). Still read empty, and now I scanned it and there was a P0461 code - Fuel level sensor circuit range/performance.
The next day they dropped the tanks again and took it all apart, they tested the senders separately off the car and the range on the Ohmmeter was correct 44-250 or something. They even swapped my old sender from the driver side back in. No luck, same code. We double checked the part numbers to make sure the senders were for the 08+ (or 07+?) for when they reversed the Ohm readings and they were correct. So now I have it back as I am driving the car to Florida for vacation, I guess I will be using the trip odometer a lot. They ordered a second set of senders again and will try again next week to swap them and see what happens. Also they are going to try and read some info from the BCM and ECU with something like a tech-2 (or whatever the latest version is called now). Oh and if I clear the code, the gauge goes to about half a tank and them 30 seconds later it goes back to empty and the code is back.
Anyone every had similar issues? I did a ton of searching and didn't come up with much that was helpful. The shop is doing their own research this week as well.
Sorry for the long post, and thanks in advance!
TL;DR - Car has P0461 code and gauge reads empty, replaced both senders already, no luck. Going to try and replace a 2nd time. Looking for any ideas.
-Jesse
10-15-2015, 07:58 PM
#3
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St. Jude Donor '15
edit: after reading all of your post I'm scratching my head a bit more.. what I would do, though, is with HP Tuners you can log fuel tank sender voltage for each tank individually. That way you can see (manually) if the senders are moving up and down according to fuel level. If they ARE moving in a repeatable manner, then it's just a matter of adjusting the tables that control how much fuel the computers thinks are in the tanks vs. that voltage. I have no idea why they would be wrong to begin with, though.
Do you have access to HPTuners or does the shop have it??
--------------
Original post:
I thought this only applied to 2005's, but when I changed the sender on the driver side on my 2005 I found that the sender worked "backwards" from the original one. It's basically a potentiometer that changes resistant based on how high/low the float is. Full and empty were opposite directions on the new one vs. the original one.
I was able to go in with HP Tuners and flip one of the tables around and make it work.. but mine was doing the same. When I got down to 1/4 of a tank or a little under the gauge started going UP instead of down, and I got the same errors after driving an hour or two.
Do you have the exact part number that was used on yours? I can try to find a stock tune for your car and see if it's possible you're having a similar issue. It sure sounds a lot like what happened on mine though.. too similar to ignore IMO
Do you have access to HPTuners or does the shop have it??
--------------
Original post:
I thought this only applied to 2005's, but when I changed the sender on the driver side on my 2005 I found that the sender worked "backwards" from the original one. It's basically a potentiometer that changes resistant based on how high/low the float is. Full and empty were opposite directions on the new one vs. the original one.
I was able to go in with HP Tuners and flip one of the tables around and make it work.. but mine was doing the same. When I got down to 1/4 of a tank or a little under the gauge started going UP instead of down, and I got the same errors after driving an hour or two.
Do you have the exact part number that was used on yours? I can try to find a stock tune for your car and see if it's possible you're having a similar issue. It sure sounds a lot like what happened on mine though.. too similar to ignore IMO
Last edited by schpenxel; 10-15-2015 at 08:03 PM.
10-20-2015, 09:27 AM
#4
Racer
Thread Starter
The shop has HPtuners. They have the car for the whole week, so hopefully by Friday it will be fixed. After driving it for over 1500 miles, the codes are still there and the level never got above 0.0 (reading it via OBD in Torque). It stayed on E the whole time, but I never really let it get much below half a tank during the trip.
Fingers crossed, hope it's something simple. Pretty much everyone at the shop has been helping out so far.
Fingers crossed, hope it's something simple. Pretty much everyone at the shop has been helping out so far.
10-20-2015, 03:21 PM
#5
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Location: Raleigh, NC
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St. Jude Donor '15
On HPT or probably with a tech 2 you can see voltages for each sender individually which should make it clear what's going on after some filling and driving to see how they move
Hopefully they get it figured out!
Hopefully they get it figured out!