A few members of the club have been inquiring about gas gauge problems in the C5. Well, I have a 2001 C5 convertible and I have experienced the fuel gauge going from 3/4 full to empty instantly at times. The problem is caused by sulfur deposits building up on the fuel sender contacts. Eventually, the corrosion becomes so bad that a sender change is needed. If you use techron before you get to that point, it cleans the contacts and the issue is improved (although perhaps not solved.) I have read on other forms that if you use certain brands of fuels in your C5, with high techron type chemicals it may improve this problem, and since I’ve switched to Shell supreme gasoline, all is good in the fuel gauge world.
Hope this helps, and if anyone has a comment, please feel free to post!
Chris…My C5 (1999 with 61k) was fine when I first got it this summer… but after using a couple of tanks of non Top Tier gas (Ultramar and Canadian Tire) I noticed my tank going straight to empty after it hit half full. I researched it on the Corvette forums, and I immediately put a can of Seafoam in the tank, and started using ESSO or Costco gas…and the problem seems to have gone away. I also put Royal Purple in it before storage…so I am hoping that is the end of that issue for me.
They say this issue is the result of using fuel that is NOT rated as Top Tier. According to this website ( http://www.toptiergas.com/retailers/ ) the only Top Tier gas stations currently in the St. John’s area are ESSO and Costco…with Shell soon joining that group when the station on Ropewalk Lane is finished construction.
The Corvette forums say that using fuel cleaners like Techron, Royal Purple, or Seafoam (which are also fuel stabilizers) from time to time and especially during storage, can go a long way towards preventing and sometimes even fixing/cleaning a dirty fuel sensor. I haven’t been able to find Techron here in St. John’s, but Royal Purple and Seafoam are available at Canadian Tire.
So I am curious, have any other C5/C6 owners noticed this issue?