Coolant temp sensor. Or knock sensor, but more likely the temp sensor. As far as your cluster, its gotta be some bad wiring. Check the harness under your pass side fender to see if it got chewed up.
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Originally Posted by PJ Prendergast
i went to a scrapyard in Kilcock today looking for my 180sx tail lights, no luck though 
...and then I wondered why I was on Stanceworks forums...