hello i have the same probleme with mine cam sesor when i put 1.8 intake cam in my 1999 elantra , yesthurday i whent to put my car on the dyno because i have adjustable sproket on exhaut and intake cam so all mark at 0 degres push 126hp at the wheel and 119 ft-pound
after adjuting cam 136hp and 132ft-pound and my check engine light was out

( parts in my engine ) cai,65mm tb and ported match the best i could ,1.8intake cam ,adj cam sproket intake and exhaut,1.8l exhaut manifold from 1997 wagon (4-2-1),2.25 inch exhaut front to back