Sponsored Content
r
Okay...let me lay this out and get your opinions. I recently discharged the battery(less than one year old Delco) by leaving the rear compartment door open. I charged the battery up and then started the car. Heres where it goes nuts. None of this was going on before the battery went dead. There may be no correlation but I would like your opinions.
The fuel guage now goes well beyond the full mark. When I crank the car, it stays there. If I shut it down and wait a few minutes to restart it, the fuel guage then works properly. Next time I shut down and restart, the guage again reads beyond full.The next anomaly occuring is the speedometer bounces 5 miles per hour above and below the actual speed. There are no wierd noises coming from the speedometer.
Again, none of this was happening before the battery went dead. Thoughts?
Scott
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
SPONSOR AD:: (Our Sponsors help support Vette Registry)
I do believe you have a bad ground connection. A bad ground makes the fuel gauge read much higher than normal, and can make gauges read poorly.
I'm not sure where it is, but would guess it is a common ground to the chassis/body system. It could be at the battery, or one of the ground cables to the body/frame.
It appears to be intermittant, and not a complete failure. A common complete failure would prevent the car from starting.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Ken is right. A bad ground will make the fuel gage read full or higher. Run a ground from the tank to the frame, and see what happens. Why it started when the battery went dead? That I can't answer.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Un plug the fuel sender wire at the tank and see if there is a short to ground in the wire going to the front. if it goes up you have a short in the wire, as above also check your ground tank strap/wire, and check that the sending unit has a good ground not just the tank.
John
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Lifetime Member
Moderator
Send PMModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 22720
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
I have to agree with everyone else. The problem most likely occurred due to the amount of time the light was on, draining the battery. It prolly drew enough amperage on the ground(s) to create a faulty connection, or finish off one that was iffy to start with.
The speedo problem is going to be a totally different issue, even tho it started at the same time. The only way it could be related would be if the speedo cable became a new ground for the gauges after the bad ground gave up the ghost....highly unlikely, but...
Start checking those grounds...
The speedo problem is going to be a totally different issue, even tho it started at the same time. The only way it could be related would be if the speedo cable became a new ground for the gauges after the bad ground gave up the ghost....highly unlikely, but...
Start checking those grounds...
Joel Adams
C3VR Lifetime Member #56 
My Link 
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
R
If you had an extra battery, you could swap it out just to see what happens. Sometimes they act funny when drained...
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Lifetime Member
Send PMGreensburg, IN - USA
Joined: 9/24/2003
Posts: 5387
Vette(s): Previous: 1984 Coupe, 1988 Maroon Coupe, 1989 Coupe, 2001 Roadster Present: 1967 Stingray Roadster, 1976 Stingray Coupe, 1989 Roadster..
Since you fiddled with the battery.... check the ground wire from the battery to the frame 1st.
Did you mess with any other areas recently as well?
Did you mess with any other areas recently as well?
Tuxblacray: She's Back In Black! Check out my pics @ My Link 
(Click on image to see a bigger version)
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
O
I know mine is the side post connection. I can tell you from direct experience (on my GMC truck) that the connectors in the side of the battery can fail and you won't know it. My truck started and ran just great, but every once in a while when you shut it off, the lights went dim, flashed, stereo came on and went off and locks would lock and unlock.
The ground side had snapped inside the battery. Contact would generally be there but not always. I finally found it one cold nite when I had just come in, shut it off, it did it's wierd thing and I had to go back out for something. She wouldn't start so I lifted the hood and checked the cables on the battery. when I touched the ground, the light came on under the hood and inside (I had left the door open).
I moved the ground and you could hear it making and breaking contact, kind of a crackly sound.
I replaced it and 500 miles later, the same thing happened. I then tried the screw in studs, but it happened a third time.
I changed over to a top post setup and have never had another problem with the battery.
The ground side had snapped inside the battery. Contact would generally be there but not always. I finally found it one cold nite when I had just come in, shut it off, it did it's wierd thing and I had to go back out for something. She wouldn't start so I lifted the hood and checked the cables on the battery. when I touched the ground, the light came on under the hood and inside (I had left the door open).
I moved the ground and you could hear it making and breaking contact, kind of a crackly sound.
I replaced it and 500 miles later, the same thing happened. I then tried the screw in studs, but it happened a third time.
I changed over to a top post setup and have never had another problem with the battery.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
r
Thanks guys. I will check out the grounds this weekend. I didn't disconnect anything when I charged the battery. I have an aircraft type connection mounted to charge the battery. Maybe I will be lucky and it's just a loose connection.
Scott
Scott
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Free Member
Send PMOak Creek, WI - USA
Joined: 5/21/2008
Posts: 2041
Vette(s): 1981 Great White Shark. Red Interior, 350/190 hp. PS, PB (SS), A/C CC, T-Tops. Served three years in Active Duty Army, then Retired Air Force after 34 years! Badger State Vettes Car Club. 175,000 Original miles!! Now own a 1998 C-5!
I would be willing to bet that you have a grounding issue. I looked for about three days to find my problem. But, I fixed it !!
Patience is a Virtue in this case.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
in Forum: C3 Electrical, Body and Interior
Sponsored Content