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Hey guys just bought a 1991 Civic and after a couple days of owning it I'm already having issues. I've been searching around and tryed a few different things but still no luck. So here's the deal, when its hot is BARELY starts and when I'm driving I have alot less power (like the cars in limp mode) and it will only rev to 3500rpm and sounds like its hitting the rev limiter. Check engine light is also on. Already I've replaced plugs and leads , cleaned the IACV, replaced the main relay, reset the ECU, tryed another ECM from anothe 91 civic and checked all other electrical connections. Any help is appreciated, thanks.