Plugged up the ecu and the car idles back and forth between 1k and 2k... What can be the problem? The car idles perfect with a chipped p28, but runs rich and It idles perfect with the odb2 ls ecu but pulls crank sensor code..

I igure there is something wrong with the ecu, but the guy that sold it to insisted that he tested it and that there is nothing wrong with it...

 

you using a P72??? a P72, P75 and P28 are the same motherboard the only differences is vtec and some sensors for it and of course they all come in both OBD1 and OBD2 if your having an idle problem with one ecu and not the other it is an ecu problem, PR4 and P61 are also integra ecu's and very different from the others though they only come in OBD1

so which ecu are you using and what harness/ motor

 

The p28 is a vtec ecu thats what I'm running now for the time being.. It causes the car to run way to rich. I also have a obd2 ls ecu which I dont want to use becuz of the crank sensor issue. Both of these ecu idles fine

So I got a obd1 p75 (which has the idling problem)

Im running a 98 b18b1 in a 97 ej8 with the d16y8 harness (which I though came with the crank sensor plug)

 

how are you jumping from OBD1 to OBD2??? your motor is OBD2 the injectors have different continuity and duration than OBD1 you need to stick with OBD2 unless you change out your injectors you need an OBD2 P72 thats your motors origenal ecu you can run a P75 its a GSR ecu if you have bolt on mods running this ecu should be fine you should beable to run that P28 thats a SOHC Vtec ecu and it not run rich. if anything it would run lean at low RPMs

 

STAY OBD2 though with the ecu's