ok here i go. my brothers civic he switched ecus from a p30 to a p28 chipped to see the difference and see if he wanted to buy this ecu from this kid. when he swaped them around he did have the neg batt terminal off. then he swapped it back after rumping on it to see the difference. now that he put his ecu back in car started ideling really bad. shot some throttle cleaner in it ran a lil better. so i decided to take the throttle off and clean out the intake and the throttle. cleaned everything out. tore the gasket on the throttle replaced that. the rpms were jumping like crazy. cleaned out the iacv. put it back on same thing. switched it with my obd2 integra iacv no difference throwing same code. checked the tps is at .50 closed 4.5 open so the tps is good. i covered the throttle whole with my hand wouldnt not stall. also pluged the iacv hole in the throttle the rpm lower really low were it should be or close to it. i let go it jumps up and down rapidly. i check the plug on the integ i got 12.3 on one pin and the other pin like 10. something so i checked it on my obd1 b16 and i get 12.4 on one pin and the other pin nothing? i have no clue what could be wrong....... i also thought maybe it had to do with the cars being obd 1 and obd 2 so thats why my iacv didnt work on the civic? i also swapped out the maps no difference. but if i leave the map unplugged it runs smoother but richer. i just dont wanna go and buy a 150 dollar iacv and turns out that wasn't the problem. and yes all this test were take at opp temp. any help please, will be great.

 

iacv's arent obd specific

clean the electrical connectors with a bit of brake cleaner and glob on some dielectric grease...might take care of it
(I had a very similar issue years ago, did the above and no problems since)

 

yo00o i got the same exact problem!!! wtf!! i already cleaned out the connectors tho..any other suggestions!!

 

take out your intake or air box. whatever you have. there should be one or two hole in the intake manifold. get a glove and plug the bottom one with your finger and if your car turns off or about to die, then your iavc, tps or something is messed up but if the idle revs higher then you have a vaccum leak. Just remove and reconnect all your hoses again

 

i tried that many times the bottom one is for cold stars the ftv what ever doesnt suck when it warms up so it has no effect its the only top whole. i plug that bad boy up it runs better but not perfect. i cover the entire throttle and it wont stall out like my integra would unless its like super car..... anyone else help please....
bump

 

never mind i figured it out.