2001 Elantra- rpms won't go over 3000
 

Hey guys, appreciate any help with this, the car can't reach 3000 rpms without the whole engine shaking violently and stalling. I thought the problem at first was a cracked exhaust manifold, changed it out (manifold and cat converter are one unit) didn't help. Checked resistance on the coil packs: primary should be .45-.55 I got .7, secondary should be 10.3-13.9k ohms I got 15.25k is this an acceptable range? What else could the problem be?:(