I have a 1997 Honda Civic I've replaced everything except for the alternator yes even the head, valves and ICS! I have a serious idle problem when I start it up it idles about at 1300rpms when I switch into drive it drops down to 200rpms I checked it out with a sensor hooked up to it then it bounces between 300-1100rpms when I start driving it the transmission sticks. Then it usually tries to die when I stop the first time I have to save it by hitting the gas. It acts like this for a while but by the time I've driven 10-15 minutes it idles okay but the steering wheel still vibrates. I have absolutely no idea what it could be and I've taken it to my mechanic that I trust and he is baffled! Any ideas would be a great help!!

. Ensure throttle cable has not popped out of throttle cable bracket.

. Clean Idle Air Control Valve and hoses:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-7.html#post1054149

. Clean throttle plate and upper and lower ports.

. Change air filter and PCV Valve.

. Replace ignitor and coil:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-4.html#post265896

. Set idle speed to specs:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563.html#post219948