Hey guys Im new to the civic scene and am still learning so bare with me. I purchased my 99 civic tonight with a b16a DOHC vtec gsr tranny. he has told me the motor is bone stock but I noticed an aftermarket fuel rail. The issue I currently have is the car has a rough idle it jumps around about 400 rpms when ideling. even if the car is cold, hot, just started or been running. He said it used to not idle at all but he replaced the iac valve and now it will idle but real rough. The reason he said was, this is becasue it is the incorect ecu for the motor and something to do with the computer being set up for a single cam not dual. He recomended the p7 something. On possibly a seperate note the speedometer is not working, dont know if its not hooked up or what. The check engine light is on and he told me it was becasue of an o2 sensor. I will have the code pulled friday to make sure and I will try and properly clean the IAC valve. any ideas though?

 

its a 99 civic b16a running a p28 it has an OBD2 adapted to an OBD1 it doesnt look like there is anything done to the p28 when you crack it open

 

as far as the ecu a p28 should run the car fine, just a tad lean (better mpg), but im running a obd1 p72 (gsr). the idle issue might be able to be fixed by adjusting the screw on the throttle body . the speedo could simply be a unhooked or non functioning vss (vehicle speed sensor) which is located on the trans. o2 sensor should be a simple fix by simply replacing it.


sorry for the massive picture below, but is a great picture for showing the location and plug on the vss

 

that is a great picture of the vehicle speed sensor and the idle screw thank you. I have checked the vss and it is plugged in and I backe doff the screw and nothing. I had a few buddys over last night and think i figured it out We came the assumption that there is a p28 automatic computer in my car p28-a52. any opinions??