Got my 87 rx7 with a 93 LT1 Z28 engine and T-56 trans. had it running great all the way up until I pulled the engine, but destroyed some pistons (should of rebuilt the engine before dropping it in), so I rebuilt the engine and dropped everything back in and couldn't get it to hold an idle and it will not rev past about 2k, no power under any load. started checking sensors, found ~0.7v reference from the coolant temp sensor and even lower coming from the intake air temp sensor. I am checking these sensors completely disconnected from the sensor itself so I am under the impression it should be approximately 4.5-5v signal directly from the ecm. tried cutting the wire near the computer and it still has the same 0.7v coming out of it. I removed any sensor with a 5v reference to see if anything else was drawing it down without changes to the IAT or CTS. I'm assuming what's happening is the computer thinks its incredibly cold outside due to the low voltage causing it to dump gas into the engine.

Any computer savvy individuals know if there's a power source going into the computer that might be throwing it off or something? I'm at the point now where I'm going to replace the ECM in thought that the board is bad. This is a obd1

Changes made were 280xfi cam, springs, 1.6 rockers, added aem af gauge (after the issue) and of course freshened the entire engine.

 

update. 3.29.14

Car is running and sounds mean as hell.

waiting for break in to see some results

 

Nice to see another set-up like mines...can't wait see more info about your adventures behind the wheel. Are you racing it or DD? Interested in knowing more about what I think is an oil res tank on pass. strut tower in engine bay- cheers!