I have 93 C1500 Suburban 5.7L K L05 with 16168625 pcm and BDJZ code. I'm trying to chase down some intermittent problems. I used Tunerpro to log.
I started @ idle and let it warm up to Engine Temp reading over 160 - IAC around 25, spark advance around 20. It never entered closed loop. As soon as I gave it a little throttle it went closed loop and then dropped out again @ zero throttle.
After driving and Engine Temp read 189, it was in closed loop @ idle - spark advance 15, IAC @ 0
I had read somewhere, I thought, that over 160 it would go closed loop, but I assume there are multiple criteria.
I've googled and not been able to find a summary of conditions necessary to enter closed loop - hoping someone with experience can point me in right direction.
Thanks
Ed