86 300zx Crank but no start issue

[isoulride]

Hello all,

Problem: Engine cranks but won't start

Facts: Spark is confirmed
Fuel pressure is confirmed
Air restriction is non-issue
Starter fluid in throttle body allows car to start for a second

ECU codes: 13 Cylinder Head Temperature Sensor
23 Idle Switch circuit
31 Air conditioning
41 Fuel Temperature Sensor

Background: I was driving along one day and the fuel pump died on me, I had been experiencing fuel pump failure symptoms for a little while (low power, backfiring at highway speeds). I got the car home and disconnected the hose at the fuel filter to check for fuel pressure, I was getting hardly any fuel flow so that confirmed the fuel pump was bad (new fuel filter). I ordered the new fuel pump, got it installed, and confirmed fuel pressure up at the engine. Now the engine cranks but will not start, but the starter fluid in the throttle body gets it to fire for a second. My understanding is this means I'm not getting any fuel in the combustion chamber, and dry spark plugs confirm that suspicion. I decided to check the fuel pressure regulator, and did so by removing the fuel return line. The regulator seems to be working because it was sending fuel back to the tank, as it should with a functioning fuel pump. That pretty much leaves me with injectors as far as I know, I have not yet tested the crank angle position sensor to see if the injectors are working properly. I am skeptical that all my injectors would fail at once, so before I spend much more time digging in that direction I wanted to get your input.

P.S
The codes were all present before this new problem, so they may or may not be relevant.

[themadscientist]

If you are getting spark then your CAS is working. Your injectors are probably not cycling. Listen for the steady clicks of a working solenoid.

Also, pull the ground cable and wait about twenty minutes then put it back on. This will reset the computer and clear the codes that stacked up while your pump was acting like a jerk.

[isoulride]

thank you for the reply, I identified what the issue was last night. I decided to try plugging in my spare computer (car came with one) and it fires up just like it should. While I am grateful to have a working car, I'm still not sure what could have caused the old ECU to fail. Took it for a drive today, seems to be fine.