[ss67ls]

i have a 2011 x3 28i 3.0 n52 engine i am having a misfire issue #4 cyl i have checked everything besides compression cause it runs great half the time and misses #4 the other half.i would think if it was a conpression issue it would misfire all the time.so i decide to check compression #4 cyl 130psi first time 135 psi second test compared to cylinder #2 180psi first test 200psi second test.so that tells me something is not correct.does anyone know what the compression psi is suppose to be i cannot find specs anywhere.the other thing that confused me is i work on hi horsepower engines and 200psi seems really high for this 6cyl engine or am i wrong.