OK, have a 91 camaro TPI 305, auto, convertible I picked up for $800, what a steal. Keeping this car pretty much stock. Here is the problem(s)

car won't run, will turn over; but not crank.

Whats been checked, replaced..

all new sensors, except the oil pressure sending unit

new fuel pump
new injectors
FPR

starter enable is bypassed as well as VATS

timing is good
Fuel pressure is sitting on 44psi
getting plenty of spark

what I recently did
replaced ecu with used but working one from ebay, used my old memcal

car started right up, ran for 3 days
however, the SES light stayed on(getting error code 12)
Idle was smooth.
Go to start car, no start, SES flickers very quickly and stays on, still turns over, but no start.

any ideas what to check?
thinking the ecu would be the culprit, could the memcal be bad?

any info is greatly appreciated, just not sure what else to check, verify.

James G

 

lets start with the basics, so you can rule out the starter since it is cranking, just not starting. we can assume you have compression seeing as how the car was running earlier, an easy one to check is ignition, pull a wire and ground it, check for spark, or ground the coil and check for a spark, if spark is good, try using a squirt of starter fluid, or check the fuel pressure at the shrader valve on the fuel rail.

this should point you in the right direction

 

Spark is fine,
fuel pressure is at 44psi, I've checked all the basics. Really clueless on this one.

 

Fuel pressure in the rails doesn't necessarily mean that the injectors are firing. I would get a noid light and plug it into your injector harness and crank it. If it flashes, you have fuel and your injectors are pulsing. If it doesn't flash, your injectors are not firing.

 

Also check the fuses for your injectors.

 

I'd try to get a different ECU AND Memcal to test the car.
Also, re-check your VATS bypass system.

 

Im having the same problem. I was driving the car today and turned the corner and died. got home and buddy told me to check the valve on the fuel rail and no pressure. ANY IDEAS

 

a code 12 only verifies that the SES light is in fact flashing codes. it isnt the actual code your getting.
when you ground the ALDL it will always flash code 12 three times, THEN it will flash the problem code three times.
if you havent unhooked the battery since it ran with the SES light, check the code again.
if you have unhooked the battery since then, it will just flash a code 12 repeatedly. i have the service manual so i can look up any code for you.

 

checked most all of the obvious problem areas. replaced with another ecm, nothing. VATS is bypassed, security light is not on. Fuel pump is priming, plenty of pressure, plenty of spark, Oil pressure doesn't get out of the red while cranking(possible OPSU??) one of the only things I haven't replaced. Id replace the MEMCAL if I ever come across a good deal on one for a 305 auto tpi.

thanks for everyone's input
James G

 

Try reading this Thread. 9 cars fixed with 7-8 different problems!

https://www.thirdgen.org/forums/tech...art-story.html

Good Luck!

 

Check the connection to ECM/ECU. Make sure the wire harness isn't loose!