Nver2loud

Hey all,
I just got back from a 1700 mile road trip luckily...About an hour into it the car was lurching on the highway, it would die for about 5 seconds at a time and then start back up, the fuel pressure gauge on the pod would sit at 0 and then jump back to 60. It did this 3 times, and I was scared but figured that the car was just cranky and I kept going. Many times throughout the trip the fuel gauge would drop to E. It did this many times and at any level in the tank, including completely full right after I left the gas station, and it says check gauges, bla bla. Anyways, Everytime the gauge went to E, i would reset the codes on the DIC and it would jump back to whatever level the gauge was at prior.
The codes I pulled are as follows

P1431 Fuel Level Sensor 2 Circuit Performance
P1433 Fuel Level Sensor 2 High Voltage
P0463 Fuel Level Sensor 1 Circuit High Voltage

Now that im back in my home state im not really scared to drive it, but am wondering what exactly is going on. Ive heard of the techron deal for cleaning the senders, but I dont think that would help with voltage spikes. Im guessing the spikes may have shut down the pump?

Ideas?

Mark C5

There are two types of common fuel gauge problems I am aware of. One is when the gauge drops to empty at a certain level and stays there. This is usually caused by a build up of deposits in the sender circuit. Sometimes it can be corrected by the use of additives such as Techron, Seafoam, etc. If not replacement of the sender is required.

The second type is when the gauge drops to empty after a certain amount of driving time, for most 40 minutes. This appears to be a firmware problem and it has been reported can be fixed by a visit to the dealer to have a firmware update performed. If you have a custom tune, be aware the dealer will need to set it back to stock to perform the update. You can get the list of updates for your car here:

http://tis2web.service.gm.com/tis2web

Neither of these problems will cause a shutdown of the fuel pump or affect the operation of your vehicle in any way.

Your trouble codes indicate you most likely have a fault in the ground circuit, especially the P1433 and P0463. Read the sticky about cleaning grounds at the top of the tech page and if that doesn't take care of the problem, unless you have access to some pretty serious diagnostic equipment, you will need to take it to a dealer.

The codes your car is throwing also should not alone cause it to shut down or run rough. This indicates to me it's a intermittent ground problem in the fuel circuit.

Best of luck.

PS Bill Curlee probably knows a heck of a lot more about these circuits than I do so if he doesn't chime in here shoot him a PM.

MarkGbe

Old topic but.... I have these same codes. Does this indicate which sender is the culprit or no?