My '91 Rx7 won't idle and I can't figure out why
 

Hi, I'm Chris. I have a black 1991 non turbo rx7 and I don't know what's wrong with it. I looked at the FAQ page and did what it said about starting it, and it worked after a few tries. Now it won't idle unless I unplug the afm. Won't even stay started. I'm at a loss here.

What exactly have you checked?

Jumper the fuel check connector w/the AFM connected and see if it will start properly. Also, w/the AFM connected and key to on, measure the voltage on the Brown/White wire at the TPS as it should read 4.5 to 5.5 volts. If the reading is rather nonexistent then the AFM is shorting out the Vref voltage which powers most of the engine sensors.

bleed the coolant. i had the same problem with my 1990 GXL.
get it running and open the cooling system at the highest point. the coolant hoses to the thermowax. let it run untill operating temp and you see only coolant coming out.

So far I've done what satch suggested. I've also unplugged the AFM and attempted to start it by manually covering the main hose. If I cover it completely for a few seconds then uncover it the car comes to life. That's the only time it comes to life

Try holding the afm open slightly with a screwdriver. If you have a large enough vacuum leak the afm won't open and activate the fuel pump

I'am Having Problems With My 1990 Rx7 Non turbo, It will Not Staying Idling, Backfires, Runs Really Rich, and One Of my Headlights Wont Go Down, Ive took it to many mechanics and they dont know what to do i got a new TPS sensor(Not Sure if the Mechanic new how to adjust it), and i got a new o2 Sensor , the problems went away alittle and came Right back if you know how to help i would love to see you PM me.

Green/Red wire of the TPS is to read 1 volt w/key to on. The engine needs to be driven for 20 minutes or so to fully warm up the engine, which is necessary before testing the TPS voltage. You can also test for error codes. There's a single Orange wire in a Green check connector near the lead coil. Ground this Orange wire to the negative battery terminal, and w/key to on, the check engine light will flash any error codes.

Also, is this car new to you such that it has been doing this basically since you got the car or have you owned this car for a period of time and this problem all of a sudden occured?