Why does my fuel gauge keep failing?!!

[tobyw]

I'm currently awaiting my 3rd instrument cluster from the dealer (still under warranty) because the darn fuel gauge quit working again this past weekend!! Something weird has to be going on, but the dealer just keeps putting in repaired or replacement clusters, saying it all checks otu OK... I'm pretty sick of paying for a nice new rig, only to have it set in their service department every few weeks for the same problem! Has anyone else had repeated troubles with the fuel gauge and/or instrument cluster failing???

[GMMerlin]

Originally Posted by tobyw

I'm currently awaiting my 3rd instrument cluster from the dealer (still under warranty) because the darn fuel gauge quit working again this past weekend!! Something weird has to be going on, but the dealer just keeps putting in repaired or replacement clusters, saying it all checks otu OK... I'm pretty sick of paying for a nice new rig, only to have it set in their service department every few weeks for the same problem! Has anyone else had repeated troubles with the fuel gauge and/or instrument cluster failing???

Most of the fuel guage concerns I have seen have been caused by an intermittant connection at the fuel sending unit.
3 clusters..tell them to stop throwing parts at it and fix the problem.

[tobyw]

I think you and I chatted about this the last time my cluster went out (around X-mas...). Anyhow, here's what happened again this time:

As we cruised approximately 200 miles, I noticed the fuel gauge was moving VERY little compared to the mileage driven. Once we got home, I was amazed at how little fuel we had burned, thinking I just got some great MPG. Anyhow, upon shutdown, I noticed the fuel gage studdering it's way down to 'E', rather than the normal gentle sweep. I immediately hit the key and fired it back up, only to find my guage only creeping up to the 1/8th mark (it has previously read just over 1/2)!! So, I tapped on the plastic cover directly above the gauge, and sure enough, the gauge jumped up to about 3/8 of a tank, which I'm guessing is a fairly accurate reading given the economy history of the rig. Now, both times the fuel gauge has failed, this is exactly what I've noticed and what has happened, and both times it was after longer trips (this sort of thing obvioulsy won't happen on 5-10 mile trips around town). Is this the sort of thing your experience has shown you to be consistant with a poor connection around the sending unit?

[tobyw]

OK, got the rig back from the dealership. They found a bad sending unit, and apperantly it's all one big happy unit, so I got a new fuel pump, sending unit, and some "module" that the service writer couldn't properly explain. At any rate, they were able to replicate my problem and diagnose it easily from the description, so it appears that things may be fixed this time...

We'll see in another thousand miles or so...

[GMMerlin]

Originally Posted by tobyw

OK, got the rig back from the dealership. They found a bad sending unit, and apperantly it's all one big happy unit, so I got a new fuel pump, sending unit, and some "module" that the service writer couldn't properly explain. At any rate, they were able to replicate my problem and diagnose it easily from the description, so it appears that things may be fixed this time...

We'll see in another thousand miles or so...

The fuel pump/sender assembly is called a module..that might be what he was talking about.

[Z71LUVA]

I have also noticed some weird things with my gas gauge. I have a 2003 Z71 Tahoe that I bought in July of "03". When I start the truck, some times the gauge slowly rises to the proper level. I first noticed it when I had the Odometer set to RANGE and the range was slowly recalculating upwards. I thought I was in the Twilight Zone for a minute there. I got to a stop sign and turned off the ignigtion, restarted and the gauge came right up correctly this time. I asked my dealer about it, but couldn't duplicate, so they shined me on. I guess I had better keep an eye on it.
Thanks for the info.