DFI and ECMDiscuss all aspects of DFI (Digital Fuel Injection), ECMs (Electronic Control Module), scanners, and diagnostic equipment. Fine tune your Third Gen computer system for top performance.
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if anyone could help it would be greatly appreciated. i have a 91 z28 305 tpi standard. the car was partly disembeled when i bought it but ran fine before taken apart.i put things back together and removed some unused plugs from the wiring harness (ie,ac plugs,tcc plug,canister purge,egr,converter solenoid,port solenoid,alternator). i traced the wires back to the ecm, cut, taped them and cut power and ground from under hood harness. only plugs that were not in use. i have a one wire alternator so that wouldn't be used. i have all ecm wiring diagrams and everything seems right. the engine cranks fine but will not start. i changed the coil, distrubitor,ecm from another running car and still nothing.i an stumped.
try doing top dead center on your number 1 cylinder yet? also how is your fuel pressure looking? i had the same issue i found out i was only getting 3psi to the rails because my pump was un-plugged from the pulsator.
i dont seem to be getting spark. my in tank fuel pump is not working so i installed an external hi pressure pump from my holley comander 950 setup, fed from factory harness and drawing and returning to a gas bottle for testing. this got fuel to the engine. with some weepage i am unsure of pressure.
i am told that my lack of distrubitor reference back to the computer is causing no spark problem and not firing my injector grounds in the computer. i tightened all fuel lines so no more leaks,pump cycles,but no fuel at the plugs.with key on if i ground injectors manualy the injectors fire. gm manual discribes this as hei problem. i am unsure if this is write but this is my thoughts now. the pickup coil turns with the engine,generating voltage that goes through the hei module and sends dis refer (0-5 volts) back to the computer allowing injectors and ignition to work. if all my wiring rings out from conectors on engine to computer(comp tested fine) then my problem must be between the pickup coil and thehei module. please help if this is wrong or if any ideas.