I have a 1988 v8 5.0 Camaro and the people I bought it from messed with the gauges and only a few of them work. The rpm and battery gauges work but the fuel, speedometer and engine temp don’t. I was planning on buying a new gauge cluster already but if I do will I have the same problem or is it just the original gauge cluster. My friend said it could possibly be the plugs the original owners didn’t plug in that say PED 36 and PED 25 that are in the engine bay and the PED 20 that is under the driver side dash.

 

Hard to say. PED is Packard Electric Division, the name of the connector mfr at that time. The numbers refer to something like the mold cavity they were made in. So there's not much info in those designations, like, they're not some kind of assembly numbers or anything like that. Also no way for us out here to know what "people" might have "messed with". "People" are notoriously variable with regard to "messing with" things. They could have done just about anything, and probably did. Or maybe, nothing. No way for us to know.

I don't know of any connectors under the dash that could affect the fuel & temp gauges but no others. The harness simply doesn't have plugs in it like that. Not sure about the speedo but I don't think so about that either. So those plugs probably won't have any effect on the gauges regardless.

The engine temp gauge has a dark green wire that goes to a sending unit screwed into the driver's side head, between the #1 & #3 spark plugs. Check there and verify that it's connected. If it's off, restoring it might fix that one. The gas gauge might be unplugged at the tank but it's not likely; that would involve AHELLUVALOTTA work, unless somebody cut the floor pan out to get at the fuel pump. If they did that to your car, then you can check back there, but if not, the gauge cluster may well be at fault. I think the speedo in 88 was electronic; it was a cable in 87, but changed at some point after that, I think in 88; so it's also somewhat likely that the cluster is at fault for that too.

It's extremely eeeeezzzzzy to change the cluster, like, takes less than 5 minutes; so if you've got one coming anyway, try it and see.

 

Perfect thankyou, I just checked out the wires and such and everything looks pretty good still so I just ended up buying a new digital one

 

Also the fuel and engine temp go up to the top when I start the car and the fuel gauge goes past full while the speedometer stays below 0

 

That might take a bit more than 5 minutes to change out. Hopefully it fixes your problems.