i have a blue 89 hatch i just got. the man that i got the car from said he put a 91 engine in 2 it. I had the car from may 11 and it was running fine. Now on friday it start 2 idle 2 high. and i cant find the problem.  can someone help me.  

i had the same problme and couldnt fint out what it was. What i did is there is (i think its a pair of nuts) on the throttle cable on the throttle body i loosened them up till the idle was at my desired RPM's. I hope that helped  

no your problem is your tps (trottle possion sensor) my ef sedan with a crx si swap did the same thing and i got a new tps and it has ran fine ever since but as long as it stops idleing high it dosent realy matter how you fix as long as you not useing ducktape lol  

check coolant temp sensor,car could still think it is cold,or stepper motor on trottle valve if u have one and of corse TPSidle control valves get blocked aswell but this would cause to splutter  

check coolant temp sensor,car could still think it is cold,or stepper motor on trottle valve if u have one and of corse TPS,idle control valves get blocked aswell but this would cause to splutter  

the intake mani gasket can be blown