car info:
1990 prelude si
b20a
auto to manual swap
d2a4 trans

i got the car on the road for the first time last month (december 2011) after having bought it in january 2011. i'm having an idle problem. if i accelerate above 2000 rpm and put the car in neutral while still in motion the engine will idle at 2500 rpm until i come to a complete stop, then after about 5 seconds at a complete stop it drops down to normal 750-800 rpm. i can rev the engine all day long while its stopped and it won't stick like it does when in motion. if i take it out of gear below 2000 rpm it will go back to normal idle rpm.

so what do you think could be my problem? i'm thinking it might have something to do with the auto to manual swap, but i'm not sure what because i took the auto trans controller out. i did leave the auto ecu in although i thought that didn't matter. maybe a bad vss? i don't know, i'm lost and could use some help.

 

I'm quite positive you need a 5spd ECU... or convert the one you have.

 

ok so i took a p06 ecu from an auto d15, and converted it to a manual. plugged it in and it doesn't stick, it does have a bit of a searching idle but i expected that. there is also a significant loss of power which i also expected. but this is leading me to believe i have a bad ecu. thoughts?

 

i wouldnt say you had a bad ecu. swapping from auto to manual while using an auto ecu would cause problems

 

yes but this car has a separate computer for its auto transmission. and numerous others have done the same swap without the problem i am having.