i have no check engine light in my 89 crx dx but when i look at the ecu i get a code 16, 17, and 20. the eld was acting up and i replced the under hood fuse box. could my ecu be storing the old codes? i also had another question about the idle. when i start my car it revs to 1500 then drops to 800 then revs up again then drops to normal. also when im driving and then i put in the clutch and in to neutral the car wants do die. the rpms drop to 500 or lower but then recovers. what can be causing all of this. thanks

 

YOu can try resetting your ecu and see if it helps...if not, then you have to deal with all the codes one by one.

 

how do i reset the ecu?

 

unhook the battery for like 2 min. thats wat i do

 

In the fusebox under the hood, pull the hazard fuse out for 10 seconds, then replace it. Turn the key to the on position(without starting it) and count the blinks to get your codes.