We present the results of simultaneous multifrequency imaging observations at 22, 43, 86, and 129GHz of OJ 287. We used the Korean Very Long Baseline Interferometry Network as part of the Interferometric Monitoring of Gamma-ray Bright active galactic nuclei (iMOGABA). The iMOGABA observations were performed during 31 epochs from 2013 January 16 to 2016 December 28. We also used 15GHz OVRO and 225GHz SMA flux density data. We analyzed four flux enhancements in the light curves. The estimated timescales of three flux enhancements were similar with timescales of ~50d at two frequencies. A fourth flux enhancement had a variability timescale approximately twice as long. We found that 225GHz enhancements led the 15GHz enhancements by a range of 7-30d in the time delay analysis. We found the fractional variability did not change with frequency between 43 and 86GHz. We could reliably measure the turnover frequency, {nu}_c_, of the core of the source in three epochs. This was measured to be in a range from 27 to 50GHz and a flux density at the turnover frequency, S_m_, ranging from 3 to 6Jy. The derived SSA magnetic fields, B_SSA_, are in a range from 0.157+/-0.104 to 0.255+/-0.146mG. We estimated the equipartition magnetic field strengths to be in a range from 0.95+/-0.15 to 1.93+/-0.30mG. The equipartition magnetic field strengths are up to a factor of 10 higher than the values of B_SSA_. We conclude that the downstream jet may be more particle energy dominated.