Engine will not trun off

[my350z8]

My son was driving his Z and it slowly died. Got it home and discovered the fuel pump fusible link was blown. Tracked down the cause to a wire shorted to the body. Repaired the wire and insulated the body wear point. Started the car and runs fine. When I turn the key off and the car keeps running. I have to disconnect the battery or pull the ECCS relay to get it to stop. Any suggestions on the cause and what to check? Any help or suggestion greatly appreciated.

[deeznuts]

What kind of "Z" do you have? 350? as your name implies. Did it do this before the wire repair?

[sergey85]

any codes? most likely something with ignition. what year is it??? we need more details about the car

[my350z8]

Sorry about the missing info. It is a 91 300Z TwinTurbo. It does not have any codes now and it did not have the any problems before the short happen.

Thanks

[sergey85]

have u had any prior maint. or tune up done before this happened like was someone working on it the day the car died . have u installed something on the car recently??? i would say check the wiring maybe something is shorting it in the ignition. man this is a tough one

[my350z8]

While troubleshooting the short problem the F25 to E12 connector was disconnected. We forgot to reconnect it and tried to start the car twice. We reconnected the connectors. When we started the car all the dash lights go out as normal. The car starts and runs fine. When I turn the engine OFF all the dash lights come but are very dim and the engine continues to run. I have to disconnect the battery or pull the ECCS relay to get it to stop. There were no codes or problems before the short. More troubleshooting shows 12 volts to eccm pin 16 when ignition switch is turned to ON or START. When the ignition switch is turned OFF (and key dremoved) there is 5 volts being supplied to eccm pin 16. This is when the dash lights are very dim and the engine continues to run. Opening the circuit to eccm pin 16 shuts everything down as it should. The manual indicates that Pin 16 is the E.C.U. power source and that it self-shuts off a few second after turning the ignition switch OFF. It appears that voltage is leaking through the shutoff circuit in the E.C.U.. Looking for a good place to get ECU repaired or a replacement ECU.

[sergey85]

i would try posting at some z32 forums and see if fanyone want to get rid of the oem ecu since most get aftermarket ones. i tried looking on google but couldnt find much(my work comp got lots of filters on so i cant access most of the sites)

[tech22]

Before you condem the ecu check the ignition switch carefully. I've seen this problem before on my 1990 300Z.