Keep Getting "1234" Code

[SonomaGTLN2]

Can anyone tell me why this code comes and goes? I originally thought it was my crank position sensor (it went away for about 5 months after I changed it out) but now it is back again. It is active when I have been cruising for 2 miles or so, then when I let off the throttle it  goes away...then comes back when I have been cruising again.  Any idea?

[jscribble]

Speedometer "A" Signal is all I can find. From here. I have no idea what that means though... Speedometer acting funny at all?

Edit: From bimmerfest forum: 1234 Speedometer "A" Signal This code is generated when the engine is under load, over 2500 RPM and no discernable speedometer signal can be detected for more than 10 seconds. Check the wiring harness, and also the instrument console

Curiosity, how are you reading the signal? It sounds to me like you're actually getting codes while driving? I wasn't aware that was possible. More code breakdown here

Good luck!

[SonomaGTLN2]

Thanks J, yeah I've looked at the cross reference tables before and I thought it was strange that it was talking about the speedo code.  Being an engine swap I do not have a speedometer running into the harness, though I didn't think the ECU was looking for the speedo signal at all...seems strange that it all of the sudden came back this weekend.

To read the codes I have been stopped with the engine off...but maybe the code is clearing itself when I let off the throttle then it isn't truly telling me the right code for what happens at that instant.

[jscribble]

Ah, then no worries. No speedo is the code you're getting, and you have no speedo, so don't mind the code.  I learned something too, so don't thank me! What did you swap the motor into?