I got an 89 ef with the stock d15b1 and before you say drop a b18 in i just need this as a daily driver while i build my ls vtec, just need this car running.
It starts fine, idles fine (for like 2 hours) but when i drive the car and come to a stop the engine either drops to extremely low rpms (can't tell exactly what it drops to, no tach) or the engine will just stall. It doesn't really want to start or go back to normal rpms once this happens. Already replaced the injectors (still dpfi, working on acquiring what i need for the mpfi swap. new fuel pump and fuel pressure regulator.
Any help would be appreciated, thanks

 

is there a CEL? if so, start there. check vacuum lines by spraying with carb cleaner and see if it revs up on its own. does it do this only when you hit the brakes? will it do it if you were to say just put it in neutral and let the rpms come down on there own?

 

All the vacuum lines are brand new and it doesn't happen everytime the car is stopped, only about half the time. I always put it in neutral and coast until i need to use the brakes, and it occasionally will do this when i let off the gas while im driving and fails to want to raise rpms, never dies completely when the car is moving.
and no, there isn't a CEL

 

check ur timing brody

 

My hatch is doing the same thing, everyone is telling me to check my vacuum lines. I think I have a bad master/booster so that might attribute to it.