I just checked my compression on my 97 civic with D16Y7 and its giving 210psi on 3 cylinders and 175 on 1 cylinder.I think the normal values should be around 135psi?the car has 190k kms on itand its total stock engine. Its lacking power and giving bad gas mileage.i just bought this car few months ago and replaced cracked exhaust manifold.It was giving really bad gas mileage before and after changing exhaust manifold,it improved a lot but still not good.Could the high readings be due to carbon in the combustion chamber due to the engine was running rich all the time bcoz of cracked manifold? also my coolant level goes down very slowly. any suggestions please? thanks in advance.