What Do You Think, Shorted Wire?

[brother_david]

Hey guys, got a little problem with my R33 S1:

Im using Q45 AMFs in my RB30 w/ RB25, they are connected through a Apexi SAFC-II to average the AFM value to the ECU, which have Nistune installed. The other day i was out driving when the BLACK/WHITE/SILVER DOTS +12V power cable to the AFMs got loose and shorted against a turbo causing the engine to cut out. This cable is also used for power supply to the SAFC.

I isolated the damage on the cable and changed the 10A 'Engine Control'-fuse which had burned and tried to turn the key and there was a buzzing sound from the passenger feet-area, my guess is either the ECCS-relay or the IGN-relay. Scratched my head, went a turn around the car checking the cable and tried again and it started.

Went home with the car, it was running as it should. Then when i tried to shut it off and the engine did but not the IGN-power, saw this since the SAFC-II is connected to that cable. I ended up taking the fuse out and obviously it died. Tried this acouple of times and it kept holding the power to the IGN, though when only if i turned the key in between.

Now to the weird stuff:

Tried to start it the day after and now when the key is in 3rd click the relay keeps the IGN power for the first time for 10 sec or so, then in some way 'restarts' and does this every 4th second. The car can start but shut down when the relay 'restarts'.

What do you think, a shorted wire to the relay? The cable i've been messing with is the BLACK/WHITE/SILVER DOTS going to the AFM. According to the wiring diagram it also goes to the crank sensor. Started the hard work ripping this cable out but i wanted to check what you guys think before i continue!

[paulr33]

check the ECU itself

open it up, look for burnt components, smell the board etc

also try bypassing the SAFC completely to eliminiate it being stupid

[brother_david]

Thanks mate! I opened the ECU and smelled the board, could maybe be a very undistinct burned electrics smell, but not enough to make it obvious. Couldnt see any burned parts etc. either.

Since i've tried with the SAFC out of the picture, no luck,

I've split the loom and followed the AFM powercable back to the ECCS relay, looks fine but i've replaced it anyway, no luck.

Tried the ground and signal ground for the AFMs, no luck.

Tried a separate signal wire to the ecu, no luck.

Next step i guess is to try some relays from a mates car and see if it could be them after all otherwise i have no other solution then trying another ECU, but a Z32 ECU w/ Nistune does unfortunatly not hang from the trees around here

Another of those weird things are that if i dont have the AFM connected to the +12v ECCS Relay wire i cant connect to the ECU in Nistune.. Might have something to do with the 'Engine Control'-fuse that burned ealier, since it too comes from the ECCS Relay.. ?

Any tip is appreciated!