The generator matrix

 1  0  0  1  1  1  1  1  1  1  1 2a+2  1  1  1  1  0  1  1 2a  1  1  1  2  1  0  1  1  1 2a+2  1  1  2  1  1  1  1  1 2a  1  1  1  1  1  1  1  1  1  1  1 2a+2  1  1  1 2a  2  1  1  1  1  1 2a+2  1  1  1 2a+2  1  1  1  2  1  1  1  1  1 2a+2  1  1 2a  1 2a+2  1  2  1  1  1  1  1
 0  1  0  0  2 2a+2  1 3a+2 3a+3  1  a  1 2a+3 2a+3 3a+3 a+3  1 a+1  a  1 3a 2a 3a  1 2a  2 a+1 2a+1 a+3  1 a+3 2a+2  1 a+1 a+2 2a+3 a+1 2a+2  1 3a a+2 2a+1  2 a+2  1 2a+1 3a+3 a+1  2  3 2a+2  0  3 3a+3  1  1 3a+2 3a+3  a  a  1  1 2a+2 a+1 a+2  1 3a+3  3 2a+2  1 a+1 3a+2  2 2a+1 2a+1  1 a+3 3a+2 2a 3a  0 a+3  1 3a 3a+3  0 a+2  a
 0  0  1  1 3a+2 3a+3  3 2a+3 2a+1 3a+3  0 2a+1 a+2  2 a+1  a  a 2a+2  a 3a+3 a+3 3a+1 3a+2 a+1 2a+2  1 2a+1  0 a+3 a+2  a a+2 2a+2 2a  a 3a+2 2a+3 a+2 a+1  3 2a  1 3a+3  2 2a+3 2a+2 a+1 2a+2 3a+1 a+1  1  0 a+3  0 2a  3  3 3a+2 2a 2a+3  1  1  a  3 3a+1 3a 2a+3 3a  1 3a+1  a 3a+2  1  1  3 3a+2  2 a+1  1  2  1  3 3a+1 2a+3 2a+3 a+2 3a+2 2a+2
 0  0  0 2a+2  0  0 2a+2 2a+2 2a+2  2 2a  2  0 2a  2  0 2a  0 2a+2 2a  0  2 2a  2 2a+2 2a+2 2a 2a+2 2a+2  0 2a 2a+2 2a 2a+2  2 2a+2  2 2a  0  2  0 2a 2a+2 2a+2  0  2  0  2 2a  0 2a  2 2a 2a  2  0  0  2  2 2a  0 2a  2 2a 2a+2  2  0  2  0 2a+2  0 2a  2 2a+2 2a  0  0 2a 2a 2a+2 2a+2 2a+2  2 2a 2a  0  0 2a+2

generates a code of length 88 over GR(16,4) who´s minimum homogenous weight is 252.

Homogenous weight enumerator: w(x)=1x^0+1146x^252+3273x^256+3030x^260+2856x^264+2382x^268+1560x^272+1251x^276+648x^280+204x^284+30x^288+3x^308

The gray image is a code over GF(4) with n=352, k=7 and d=252.
This code was found by Heurico 1.16 in 1.95 seconds.