Discussion:
Rough idle on cold start

I have a Komatsu FG18SHTU-20 with a K21 engine, that when started cold, the idle will hunt for about a minute between 700-950 rpm before leveling out and running great. The O2 sensor has been changed(aftermarket),the MAF, regulator and throttle body have been cleaned, as well as the screen between the regulator and throttle body. I have a hand set and and have done relearn on all I can, with the exception of the idle air control. Whenever I try to relearn the idle air control, it just tells me to wait. Could the engine be doing a relearn on that in the time it is taking for the idle to stop hunting? Or could the hunting be caused by something else?
  • Posted 24 Jul 2022 03:22
  • By lvscr
  • joined 24 Apr'14 - 41 messages
  • Idaho, United States

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Aichi SR10C1SM
Yokohama, Japan
Used - Sale
Rail King RK330
Coraopolis, Pennsylvania, United States
New - Sale
Movers & Shakers
Rodney Grant Rodney Grant
Chief executive officer, Hire Industry Association New Zealand (HIANZ)
Director of sales and operations planning, Hyster-Yale Materials Handling
President, Advanced Intralogistics
Chief development officer, DHL