Hello, I am new to this site, so apologies if this isnt posted in the right thread. as the title suggests my RX7 (1987 FC NA and auto trans) runs very poorly and im not sure whats wrong with it. Disclaimer the gas tank is currently a bucket in the trunk with the fuel pump and fuel return line in it. when i start the car (or at least when it turns on as sometimes there is no electricity to the car, no dash lights/noise etc) the idle rpm jumps to 2.5/3k RPM i think the car is running too rich because it backfires like crazy when i rev it, after that the rpms slowly start going down, coolant gauge always shows cold to basically 0 degrees the oil pressure gauge showed high oil pressure before (like 90 i think?) And now it shows almost none (at the bottom like 30 maybe? Sorry for not being specific dont entirely remember) and the battery voltage meter goes down with the amount of rpms, after about 35 minutes or so of the rpms slowly dropping as low as under 100 rpms, the car dies, and the battery is completely dead. Ive been slowly fixing the car for 7 months now and if this turns out to be something serious that requires a rebuild then i will be revoking my RX7 club membership and joining the mk3 supra/corvette forums. Thank you

 

welcome to the board.

you can get a copy of the FSM here: Foxed.ca

i would start with the charging system. doesn't sound like your alternator is working, and so nothing's going to behave consistent or normal until you fix that.

 

I was going to check the grounds on the alternator, to see if it works, could there be something wrong with the TPS?

 

could there be? of course. however, it would probably be best if you sort out the electrical issues first, then try to address other things.