dieselmiata

1992, no mods, was running fine until last night as I prepared to turn a corner I pushed in the clutch, heard a weird noise and she died. She cranks fine, but never fires up. Not sure if related but earlier that day I used a jumper to bypass the Clutch interlock.
Flying_Solo was around the corner, so he towed me home and we got to tinkering, here’s what we have checked so far.
No CEL codes. The PCM seems to be fine as I still get the CEL light when car is turned on, and get corresponding codes when I unplug things like the CAS. Half tank of gas, pretty sure it was good as I’ve been running on it for half a tank.
I took off the timing belt and crank boss to check and timing is fine, the gears line up to I and E as the engine is at TDC. The crank pulley wobbles a little but I’m chalking it up to a bad pulley as the keyway is in perfect condition.
Has good spark from all 4 plugs. I pulled them all and fired them with a tester, bright steady spark. Coil packs tested fine.
Pulled AFM off and tested it according to the Haynes Manual. Everything is fine.
Fuel pump tested fine, injectors are clicking, circuit relay tested good, fuel pressure appears to be good Fuel shot across the room when I pulled the line and turned on the pump. Using a stethoscope I heard fuel flowing from the pump through the fuel rail and through the return line. If I pull the plugs after turning it over they are wet with fuel so I’m pretty sure it gets gas.
I’ve checked ALL fuses both under the hood and under the dash. Replaced the MAIN and Fuel Injection relays just to be safe. Still nothing.
I’m at a complete loss now. She cranks fine and steady but never fires up. I’ve read about every thread I can find about this and still nothing works. Any ideas?

Track

try another CAS. you may not be getting a code for it, but that doesn't stop it from not working properly.

MF-Brain

iTrader: (1)

do you ride the clutch pedal when you turn?



The only thing you didnt do is check for spark. Make sure you're getting spark when cranking, if not check your ignitor, cas, and coilpack.

dieselmiata

No, I was downshifting. I never ride the clutch.

Spark was checked at all 4 cylinders. Bright steady rythem to the spark on all 4.

Correct me if I'm wrong, but if the CAS was bad wouldn't I not be getting spark?

MF-Brain

iTrader: (1)

correct.

so you have spark, fuel, and air....hmmm


is the pump priming on key on and running during cranking?

dieselmiata

I believe so. I tested all the connections on the fuel pump and it's getting the correct voltage. When I jump the GND/FP it runs. Is there a better way to test for it?

RedTurboMiata

did you try starting it while you had it jumped?

MF-Brain

iTrader: (1)

did you crank it while f/p and gnd were jumped?

dieselmiata

Yes, no change.

RedTurboMiata

try taking the power off and let the computer reset. then try