Nistune Forums

This is only during cold starts. I crank it over and it pops off beautifully, runs great for about 5 seconds and then the A/F just dives lean. I haven't been able to pinpoint at what temp this issue subsides. I have adjusted cold/warm cranking enrichment tables and they are identical to each other. I will attach the log I took of this happening. From what I can see (pretty novice opinion) there are no major changes to any of the data being logged that could cause this large of a lean surge.


Edit: I did some testing. It idles and cruises great with my K at 283 when warm. I adjusted it while cold starting it and was able to get it stoich with a K of around 443. Obviously I won't want to do that everytime I start it cold. I just am out of ideas as to what tables have affect on a cold, running, motor.

87 Z31
Innovate MTX-L
Holset Hx35
550cc injectors
Stock AFM

What about temp enrich table? As it start ok,crank values should be ok. If you improved it by k,same thing should be possible by altering temp enrich.values. You will get longer inj.pulsewidth for cold afr to make it more rich,without altering k. And check if temperature reported by ecu is matching reality.

I don't see a table labeled "Temp Enrich" exactly. Just "Enrich (Cold Crank)" and "Enrich (Warm Crank)"

I made some serious adjustments to the Cold & Warm Enrichment and I think I'm on the right track now.

I noticed today that when my temp got to 140 the car's idle smoothed out as if it switched to a different map. I haven't read anything about this situation anywhere. Maybe Matt can shed some light on the what is happening?

Those tables stop being used around 80 degC