Gas Gauge Issues
 

Hi folks, we have a 02 buick regal that I replaced the fuel pump assembly that included the sending unit that I thought was defective. The fuel gauge had been moving all over the place before staying on full. the new setup didn;t solve the problem, it's is still stuck on full. Any ideas where to start?

I would check it at the cluster and work my way back to find the problem.

I agree with carfixer007 . It sounds like the control board in the cluster going bad.

My 1997 LeSabre did the same thing with the speedometer as in: It would indicate a wackiness as if it was reinterpreting the actual speed with the laws of the 8th dimension. It would whack the ends of its range of travel while attempting to point at all of the stars at once. It's mood would change with temperature, but only in degrees of wackiness.

I got a young donor gauge cluster and swapped only the control board and voila' no more problem for probably 100,000 miles so far.

cluster
 

check at the cluster like look for melted solder loose wire?

Most of the time you can't see the damage on the cluster board. If something is melted etc. there's probably a bigger problem in the electrical system that caused it.

I agree. To the untrained eye, a circuit board is just a board with weird objects on it.

I'm suspecting either the sending unit harness is chaffing ground, or the logic circuit in the cluster is fubar.

You can take it to the dealer and they can put the Tech2 diagnostic scanner on it and do a cluster test. Standard diagnostic fee should apply at the dealer(1 hour min time)

Or, you can go to a junkyard and pull one. Again, back to the dealer to program the mileage.

Oh yeah, that's right: a 2002 Regal has an electronic odometer, doesn't it?

Remember, mine has the gauges not digital, if that matters

I can't tell you how many of these clusters I've 'rebuilt'. Pull it and soldier all grounds and any joints that look cold or bad. Be sure to use heat sinks if needed.

They are still electronically controlled with stepper motors and integrated circuits etc. that bridge the gap between what the computer is thinking and what is being displayed mechanically. At this level is is actually an additional conversion to display with mechanical gauges than with a "digital" solution. There's an IC on your board that tells your stepper motors how many fractions of rotations to turn in order to move the needle to the appropriate position.