My car is 97 civic ex,condition is very good, but when I was in traffic or teach my wife practice back-in (always step on the break pedal,driving very slow),after about 10 minutes, the ideal speed will be very high, about 1500rpm-2000rpm, so when you change gear, it feel not comfortable. When the ideal speed was high, if I l let the accelerate pedal a little bit up (by my foot, ), it will down to 900rpm, but when you continue practice back-in, it will still back to high ideal speed quickly,but a moment later after you drive fast along, it iwill be back to 900rpm(normally), every thing will be good, is this nomally? or what kinda of reasons cause this problem? Tks a lot!

 

faulty brake booster (diaphram on inside) or check valve perhaps...

 

I don't really understand the question. It idels high? check the sensors...iacv blah blah ...clean the tps...how many miles on the car, is it a d16y7 or y8 (dx or ex)