Starts then dies, no matter what I do
 

FC3S 88 rx7 N/A manual transmission latest engine from an 86 rx7 N/A manual transmission

Welcome folks, I've been in this thing's fuel pump, plugged back in the computer under the passenger floor (along with other connectors that control something or another. Spark plugs, spark plug wires, ignition coils, throttle position sensor, mass air flow sensor, fuses from both boxes, cleaned the grounds and where they bolt to, made sure the crank angle sensor was properly set, these are just off the top of my head.

I've searched the forums every time I come to work on the car to find tips or something else to check, but no matter what, it still dies. The only time it stays on is if I'm on the accelerator and even then, it doesn't always detect when I step on the gas. Either it's a very late response or no response at all (and stalls itself out). Friends have told me I have a vacuum leak, so I took apart the intake today, cleaned up, checked the lines, everything seems fine but this issue still persists

Help?

have someone keep it running while you spray for vacuum leaks.

Thanks, I'll try that

this "latest engine", any idea if its actually a GOOD engine? or are we shooting in the dark?

Compression test?

there is a big rubber hose on that flexible snorkel pipe that goes to the AFM..Check that it is hooked up.
Also IF your AFM is not plugged in the car will start and die..over and over again,until it gets plugged in!

Lol, it was a running engine (daily) before we pulled it from my friend's FC

**UPDATE**

Embarrassing but I mixed up two vacuum lines around those four connectors on the rat's nest. It is able to idle but that throttle response is now 50/50 in responding on time (or not).

I haven't gotten around to the compression test yet, and of course, I'm keeping an eye on that air flow meter haha

Also I noticed a "new" rumble and ticking sound coming from what sounds and feels like the rat's nest. Would anyone know if that might be part of my problem?