What is the function of the idle air control (IAC) valve or motor?

Dec 14, 2022 ... I would download ISTA and get the codes that causing the DTM. Post them here. Did you torque the spark plugs when you installed new ones? Or did ... Oct 21, 2011 ... I believe if the engine is running too rich at some point it can cause a rich misfire condition in which the HC levels begin to rise along with ... Feb 2, 2019 ... Carbon is relatively conductive and a thick enough coating will cause a voltage loss across the spark plug gap (=weaker spark = more fouling = ... Aug 20, 2014 ... So basically the problem is the same as what my friend experienced. What is not the cause in my opinion: Compression. 6 bar on both sides. It ... ... spark plug because the exhaust smelled quite rich. The plug (original Bosch WR7 DDC4 with two earth points) was heavily fouled with carbon. I cleaned it up ... May 13, 2021 ... Carbon fouling on a spark plug is caused by a problem with the fuel that you use. Often, we describe it as a fuel mixture that's too rich, which ... Jun 6, 2011 ... Usually fouling is caused by too rich a mixture or weak spark, afaik. I think getting the right adjustments on the carbs, ensuring the proper amount of spark. Apr 29, 2012 ... Thanks Jim. I'll check the air control cable. That sounds like a likely cause. There seemed to be good tension at the lever but of course that ... Jun 25, 2013 ... Carbon fouling occurs when the spark plug firing end does not reach the self-cleaning temperature of approximately 450°C (842°F). Carbon ... Mar 11, 2011 ... If the deposit is hard baked-on, black carbon, the result is indicative of use of too cold a plug. ... cause for a lot of fuel going into the mix.