98 ex still having idle problems

1 month ago my car sometimes would idle at 1500 rpms and the cel went on and when my car would do this it would jerk back hard when i pressed or let go of the gas. So i replaced the air idle control valve and the cel went off and drove fine for a week, then it did it again and gave me the same code off the cel, what could be my problem?

What was the exact code number? P???

dont remember the code number, but it was idle control system malfunction.

code is P0505, had 7 possibilities of what the problem could be, my mechanic at work checked all of them and everything is working fine, what could the problem be? Should i start saving for a b18?

Hmm did you check for any vaccum leaks? Intake gasket, Throttle body gasket, etc.

checked, throttle body clogged/in proper adjustment, vaccum leaks, throttle body position sensor, IAC Manfunction, ect.

alright here is exact list of what my mechanic checked and everything is working perfectly, but yet the idle is fucked up, IAC valve mechanical malfunction,throttle body clogged port/improper adjustment, intake manifold gasket leak, intake air hose loose leakage, vacuum leak, ECT sensor incorrect output, throttle position sensor incorrect output.