I have a weird problem and an even weirder fix. My datalogging gets wonky, only MAP and O2 update. The only way I have figured out how to fix this is to pull the memcal off the adapter and put it back to stock. Then start it, then put the memcal back on the adapter and the emulator or custom chip back in.

This doesn't make much sense to me, but it obviously works. Can someone suggest what is going on and a better way to get data logging back?

Thanks.

 

That is odd? If your data log is "wonky" you should be able to dissconect and reconnect from tuner software and do the same thing...

Unless... since this is a conversion... maybe you have a wiring issue and when you turn key off it is turning fuel and/or ignition off but leaving ECM power on? There is a power wire to ECM/PCM that is always 12 volt but another that is 0 volt key off and 12 volt key on, all the way to start and back to on without interuption. In a conversion it is easily done by using the wire that feeds points with resister removed or electronic ignition feed wire to turn on relays.

 

It would be easier for me to pull the cables from the ECU, which I did try, because that was easier. But the problem stays until I replace the stock memcal.

I will go back over my wiring again, but this would be the 3rd time. The only possibility is a relay issue like you say, because other than that the harness is untouched. I have two relays - one for power and one for fuel. But that still does not explain why it lasts past a physical disconnect. I even tried the fuse at the battery.