I have an 86 GXL with 33,7XX miles that sat for 21 years. I have nursed it back to health and it is now drivable, but the fuel gauge and oil pressure gauges do not show anything. I assume that the oil pressure gauge is just a bad sending unit, but could it be anything else? I tried looking through the wiring diagrams in the haynes manual, but I couldn't find where the fuel gauge problem may be. I am also having the 3800 rpm hesitation and I will be regrounding everything as the FAQ suggests tomorrow, is there anything else that I can do to fix it?

 

Ok I just bought my first FC monday so I've just learned on how the interior is...I got a lot more to go. (Been toying w/ my brother's FBs) Now if the fuel gauge is like any other vehicle then the float is probably stuck or broke. 3800 hez....no ideal.

 

I re-grounded the ECU ground on top of the engine block per Aaron's instructions, and I still have the hesitation. When I took it out to test it, it wouldn't idle properly and kept dieing. When I got home I noticed more smoke than usual (I ran a somewhat hefty premix for the first tank) there was massive oil loss (at least 3 quarts) and what appeared to be blow back all under the car covering the exhaust. What could cause a leak this massive all of the sudden? I checked the oil level like 5 days ago and haven't done more than 15 miles since then. I have cardboard under the car now to try to locate the leak, but if anyone has some ideas in the mean time I would appreciate it.

 

you are on track with the cardboard.
I would be checking the oil lines that go to the engine and the cooler.The lines can deteriorate with age and also the Crush washers in between the line and the cooler/engine may need replacing.
You fuel gauge problem could be a bad ground at the tank,and you oil sender wire may be off,That is located around the oil filter pedestal at the side of the drivers side rear housing.The sender looks like a Bell.(single wire going to it.)