I need lots of help. My '84 Z28 with the L69 and 700R4 just became my only car and daily driver. I will number my issues ...

1) Speedometer is 10mph lower than reality (i.e. it says 45mph, but it is really only traveling at 35mph). The speedo has a slight vibration when in motion.
2) Trunk lock, when I lower my license plate there is a hole for the locking mechanism and about 3 inches into the trunch you can see the latch for the hatch and a simple twist of a flathead screw driver will pop the rear hatch up. I have bought the parts needed for reassembly from the dealer, but I don't have a clue where all the parts go. Does anyone have pictures, diagrams, instructions, etc.?
3) My temp guage doesn't work and my electric fan doesn't work. The temp guage is pegged all the way down, and doesn't move for squat.
4) What guage steel should I use to fill in huge gapping rust holes in my trunk and along the floor of my car (outer edges of floor pan near where the groundfx bolt onto.

Thanks ahead of time!

 

For question 1 do you have the right size tires? If yes, you might have the wrong speedo cable on the car.

For question 2, go to a gm dealer and ask them to print the parts page for that area. It will show all the parts and how they fit on the car.

Don't know about the rest....

 

I am using the factory size 215.65.15 on all four wheels and the speedo cable appears to be the original cable. This car was a pile of rust when I found it so everything looks ancient (as if the car sat in a salt bath for 20+ years).

 

1. Another thing on the speed could be if the car ever got a gear change/axle swap.

1A. If that is orginal, then either the cable is bad and needs replaced, or the speedo itself is bad and either "deal with it" or swap it and have a car that has the wrong milage.

2. Bill has a good idea, or if you can go to a junk yard in the area, go look, inspect, and maybe buy some parts.

3. I dont know wiring on an 84 car. I would start with replacing the sensor(s) and inspecting the wiring.

4. This depends on how many tools, and how much metal work knowledge/experience you have. The trunk floorpan can be bought from several vendors. Same with floorboards. But it takes time and several tools to install this stuff.