Alright, here's a problem that I've been encountering. On initial cold start. Car has sat for 5 hours. Temp is cold so car is definitely starting from cold. It'll start up fine and it'll go fine, and always like clockwork probably within the first 30 seconds to a minute of warm-up. Somewhere in that range like clockwork everytime I'll hit a really dull spot where my throttle response, and power seems really sluggish. If I give a little more throttle it's like there's no problem. This is only for just a few moments.
I want to say I noticed this after I messed with my timing maps. I went through and basically tried to put the best of the timing maps together out of the 84, 87, and 88 Z31 ECU images. The best I can guess is that it has something to do with the higher low end timing that the 84 had matched with the 87-88 ECUs cold timing advance possibly running too much timing and hitting a lean spot? Basically 3-wire O2 sensor heats up too quick and goes to switch to closed loop, causes the mixture to lean out a bit and I'm still running the timing advance with the higher low end timing causes my dull spot? I figure I'm going to try with just a straight untouched 87 image, and then try it with a straight 88 image and see if the problem occurs.
Warm-up dull spot
Moderator: Matt