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M50 Idle and O2 problems

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    M50 Idle and O2 problems

    Okay Ill start from the beginning. I have a 3.0L M50 that I went out to start the other day and drive to work. It runs MS2 extra v3 board. I have been driving the car with no issues for several months. Started it up and the rpms jumped to 2k and didnt settle back down to normal idle rpm (750). After a few seconds I started seeing smoke from underneath the hood. Quickly shut off the engine and opened the hood. Saw a little oil seepage from the valve cover gasket on the exhaust manifold. Figured this was it, so I got a new valve cover gasket and spark plug gaskets and resealed it. Started back up and same thing, 2k and smoke from the engine bay. I got my tuning laptop out and noticed my O2 sensor was pretty much staying at 10.1 no matter how much I increased or decreased the req fuel. Req fuel was originally at 25, which is extremely high for 21.5lb injectors but thats what the engine seemed to need to run and my AFR was just fine. Anyway, dropped the req fuel to 10 and the smoke when away, exhaust is not the greatest so it could have come from here. Let it warm up but the idle was still at 2k.

    I adjusted the PWM Idle duty cycle but this doesnt seem to be affecting the rpm at all. The idle control valve used to function properly, I could raise and lower the idle rpm by adjusting the PWM idle duty cycle. So either my idle control circuit is bad or the idle control valve is bad. What is everyone using for idle control?

    I have an LC-1 wideband with a gauge. Im going to go out and double check the output voltage ranges for output 1 and 2 to make sure its not sending a narrow band signal when it should be sending a wide band.

    Any other suggestions?